OPINION

JENKINS, J.—

On the evening of February 19, 2007, defendant Richard Tom, while driving at a high rate of speed, broadsided a vehicle driven by Loraine Wong as she was making a left turn from Santa Clara Avenue onto Woodside Road in Redwood City. Wong's two daughters, Kendall (aged 10) and Sydney (aged eight) were riding in the rear passenger seat. Sydney was strapped into a booster seat on the side of the vehicle that bore the brunt of the impact. Sydney died as a result of injuries sustained in the collision. Kendall survived, but sustained serious injuries.

As a result of the collision, defendant was charged with gross vehicular manslaughter while intoxicated, driving under the influence causing harm to another, and driving with a blood-alcohol level of 0.08 percent or higher causing harm to another. Defendant pleaded not guilty to all charges. After a lengthy trial, the jury acquitted defendant on all alcohol-related charges but returned a verdict of guilty on the lesser included offense of vehicular manslaughter with gross negligence.

In case No. A124765, defendant appeals the judgment imposed following his jury trial conviction. Defendant asserts multiple grounds for reversal of the judgment, including deprivation of constitutional rights, prosecutorial misconduct, improper admission of opinion testimony, prosecutorial failure to disclose exculpatory evidence, ineffective assistance of counsel, and sentencing error.

In case No. A130151, defendant collaterally attacks the judgment by way of a petition for a writ of habeas corpus, asserting as prejudicial error many of the same issues raised in his direct appeal. On the court's own motion, we consolidated the two cases and deferred our determination of whether to issue an order to show cause on defendant's writ petition until we considered the issues raised on appeal.

Having considered the contentions raised by defendant on appeal, we conclude that the prosecution violated defendant's Fifth Amendment privilege against self-incrimination by introducing evidence at trial of his postarrest, pre-Miranda silence as proof of guilt. (Miranda v. Arizona (1966) 384 U.S. 436 [16 L.Ed.2d 694, 86 S.Ct. 1602].) We also conclude that defendant was prejudiced by this violation of his Fifth Amendment right. Accordingly, we reverse the judgment and remand the matter for further proceedings consistent with this opinion. We dismiss the writ petition as moot given our resolution of defendant's Fifth Amendment claim.

PROCEDURAL BACKGROUND

In an amended felony information filed on October 7, 2008, the San Mateo County District Attorney (DA) charged defendant with vehicular manslaughter with gross negligence while intoxicated (unlawful killing of Sydney Ng) as a proximate result of violations of Vehicle Code sections 22350 (basic speed law) and 23103 (reckless driving), in violation of Penal Code section 191.5, subdivision (a) (count 1); driving under the influence and causing injury to another, in violation of Vehicle Code section 23153, subdivision (a) (count 2); and driving a vehicle with a blood-alcohol level of 0.08 percent or more and causing injury to another, in violation of Vehicle Code section 23153, subdivision (b) (count 3).

The DA alleged that the offense charged in count 1 was a serious felony in which defendant inflicted great bodily injury on someone other than an accomplice, pursuant to Penal Code section 1192.7, subdivision (c)(8). The DA also alleged with respect to count 1 that in the commission of the offense defendant personally inflicted great bodily injury upon Loraine Wong and Kendall Ng, within the meaning of Penal Code section 12022.7, subdivision (a).

The evidentiary phase of defendant's jury trial began on October 16, 2008. The jury delivered its verdicts on October 29, 2008. The jury found defendant not guilty of count 1 and acquitted him of the lesser included offense of committing vehicular manslaughter while intoxicated with ordinary negligence. However, the jury found defendant guilty on the lesser included offense of count one, vehicular manslaughter with gross negligence, in violation of Penal Code section 192, subdivision (c)(1). The jury also found true the allegation that defendant personally inflicted great bodily injury on Kendall Ng but found the same allegation had not been proven with respect to Loraine Wong. Furthermore, the jury acquitted defendant of the charges in counts 2 and 3 and also acquitted him of lesser included misdemeanor offenses related to those counts.

On April 22, 2009, defendant filed a motion for a new trial based on newly discovered evidence. The trial court denied the motion for a new trial and proceeded to sentencing on April 24, 2009. The trial court sentenced defendant to the middle term of four years on his conviction for vehicular manslaughter with gross negligence and imposed an additional term of three years for the personal infliction of great bodily injury upon Kendall Ng, for an aggregate term of seven years in state prison. In addition, the court ordered that defendant pay restitution in the amount of $147,860.82. Defendant filed a timely notice of appeal on April 27, 2009.

FACTUAL BACKGROUND

At trial, the prosecution presented testimony of several police officers who described the scene at the collision, as well as the ensuing investigation culminating in defendant's arrest on alcohol-related charges. Other prosecution witnesses included Loraine Wong and Peter Gamino, a retired police officer and friend of defendant. Gamino was with defendant during the evening the accident occurred and was driving another vehicle behind defendant's vehicle when the collision occurred. There were no third party witnesses to the collision and both sides presented expert testimony regarding the speed of defendant's vehicle at the time of the collision. We recount the pertinent trial testimony below and provide more detail where required to resolve the issues raised by defendant.1

The Accident

On the evening of February 19, 2007, Loraine Wong decided to take her daughters, Sydney and Kendall Ng (ages eight and 10), to her sister's house in Sunnyvale for an overnight visit. Wong drove a Nissan Maxima automatic sedan to her sister's house that evening. Kendall was seated in the rear passenger side of the Maxima and Sydney sat in a booster seat next to Kendall. Before departing, Wong secured both girls in their seatbelts and fastened her own seatbelt.

Wong took Santa Clara Avenue to Woodside Road en route to her sister's home. Upon reaching the intersection of Woodside Road and Santa Clara Avenue, Wong planned to turn left and proceed on Woodside to the southbound I-280 on-ramp. Wong had driven this route to her sister's home hundreds of times during the 15 years she lived on Santa Clara Avenue. Wong backed out of her driveway and called her sister on a hand-held cell phone to let her know "we were on our way to her house." The evening was chilly and clear. Wong spoke with her sister for a few minutes until she came to a full stop at the intersection of Santa Clara Avenue and Woodside Road. Wong recalled that her headlights and left-turn indicator were on at this time.

At this point, Wong was finished talking with her sister but had the cell phone in her hand. She began to inch forward, and looked to her left and observed the next cross-street, Alameda de las Pulgas. Wong then looked right and left again. Seeing no oncoming vehicles in either direction, she eased onto the accelerator pedal to execute a left turn. As she began to turn she "saw a big flash of light" and was struck by a vehicle on her left (driver's) side. Before she saw the flash of light, Wong heard no sound associated with a car braking or a horn. She did not see headlights to her left and never saw defendant's car. Wong estimated she was going about 15 miles per hour at the time of the collision.

After the collision, Wong discovered that her daughters were injured. She yelled their names; Kendall responded, but Sydney did not and never regained consciousness. Shortly, medical personnel arrived at the scene and extracted Wong and her daughters from the vehicle. Sydney and Kendall were transported to Stanford Hospital. At the hospital, Wong was informed that Sydney had died.2 Kendall sustained a cut to her forehead that required 30 to 40 stitches, a broken arm and an injury to her neck, and Wong suffered a broken rib and finger. Wong was released from the hospital on the night of the collision but Kendall remained in the hospital for a week.

Retired San Francisco Police Officer Peter Gamino testified that he had known defendant for about 20 years. Gamino was visiting California and staying at defendant's house on Sequoia Avenue near Woodside Road when the accident occurred. On the evening of the accident, Gamino and defendant had a couple of cocktails before dinner. They ate around 7:00 p.m. and finished about half an hour later. After dinner, they drove in defendant's Mercedes to defendant's son's house in order to pick up a Toyota Camry. After retrieving the Toyota, they left. Defendant drove his Mercedes and Gamino drove the Toyota. Gamino followed defendant onto Woodside Road. Gamino was about 200 yards behind defendant driving at a speed of about 40 miles per hour when he observed "dust and dirt ... all over the place," indicating that a collision had occurred. He made a U-turn and circled back to the collision scene to check on defendant. Defendant was groaning in pain, and said, "I didn't even see it."

Postaccident Investigation Through Defendant's Arrest at the Police Station

Sergeant Alan Bailey and Officers Price and Felker of the Redwood City Police Department were among the first law enforcement officers to arrive at the scene of the collision. Sergeant Bailey arrived at 8:30 p.m. and took charge of coordinating the investigation. He observed that conditions were dry and it was a "pleasant evening." Bailey noted Santa Clara Avenue is a two-lane roadway, running east-west, which intersects Woodside Road, a four-lane roadway running north-south. Defendant's silver-colored Mercedes E320 was a considerable distance north of the Woodside Road/Santa Clara Avenue intersection. The Mercedes had sustained major front-end damage, the windshield was cracked and it had a couple of flat tires. Defendant was seated in the driver's seat of the Mercedes with the airbag deployed. Paramedics were attending to defendant and Officer Price was standing beside the vehicle.

Bailey parked near defendant's vehicle, and walked south through a "very large debris field." He noted that the other vehicle involved in the collision, a 1996 Nissan Maxima, had sustained "major, total damage." There was massive intrusion to the Nissan's left rear passenger door, the entire rear end of the vehicle was "destroyed," and the front windshield, the back window and the left rear passenger window were all shattered. The occupants of the Nissan had been removed from the vehicle by paramedics by the time Bailey arrived.

After examining the scene, Bailey was told by several officers that defendant was now seated in the Camry driven by Gamino. Bailey directed Officer Felker to place defendant in a patrol car. Bailey also told the officers to ask defendant if he would go to the station in order to make a statement and give a voluntary blood test. Defendant was placed in the patrol vehicle at 9:30 p.m., transported from the scene at 9:48 p.m. and arrived at the police station at 9:57 p.m. Bailey received no information at the scene as to whether defendant had shown any signs of intoxication.

Bailey arrived at the police station about 10:00 p.m. He entered the police station and spoke with David Redding, the phlebotomist. Redding told Bailey that he could not draw a sample of defendant's blood because defendant was not formally under arrest. Redding advised Bailey that defendant would need to be transported to the hospital for a voluntary blood test. At approximately 10:30 p.m., Bailey went to speak with defendant about obtaining a blood sample. He found defendant in an interview room with Officer Price. Defendant asked Bailey to use the restroom. Bailey consented and escorted him to the restroom. During defendant's interaction with Bailey at the police station, defendant never asked Bailey about the occupants of the other vehicle.

Officer Price arrived at the accident scene and was directed by Officer Felker to contact defendant. Price found defendant sitting in the driver's seat of his silver Mercedes being attended by two paramedics. Price spoke briefly with defendant. About 10 minutes later, Price observed defendant walking around. At this point, he (defendant) was accompanied by his girlfriend. Paramedics were trying to convince defendant to go to the hospital but defendant did not want to go. Defendant was limping slightly but otherwise "seemed okay."

Later, Price observed defendant and his girlfriend with Peter Gamino, all sitting in the Toyota Camry, which was parked in the cordoned-off collision scene. Defendant was sitting in the front passenger seat, Peter Gamino was sitting in the driver's seat, and defendant's girlfriend was sitting in the rear seat of the car. While Price spoke with Gamino, he observed that defendant appeared calm. Defendant asked Price if he could walk home because "he lived only half-a-block away." Price told defendant that he had to stay at the scene because the investigation was still in progress. During this conversation, defendant did not ask about the condition of the occupants of the other vehicle.

Officer Felker testified that at approximately 9:48 p.m., he transported defendant from the accident scene to the police station to obtain a blood sample and a statement from defendant. Defendant was not handcuffed during the ride to the police station and his girlfriend was allowed to accompany him in the patrol car. Defendant appeared irritated that he had to go to the police station and asked Price why a blood sample could not be taken at the scene.

Officer Price arrived at the police station shortly after 10:00 p.m. and learned that a blood sample could not be obtained from defendant because he was not under arrest. Price spoke with defendant about going to the county hospital for a voluntary blood draw. Shortly after speaking with Price, defendant was escorted to the restroom by Sergeant Bailey. When defendant was finished in the restroom, Bailey escorted him and his girlfriend to an interview room. Officers Price and Gomez entered the interview room and observed defendant talking on his cell phone. While defendant conversed on the telephone, Officers Gomez and Price both detected an odor of alcohol from defendant. Price then had defendant take a series of field sobriety tests (FST's). Based on the results of the FST's, Price concluded defendant was under the influence of alcohol at the time of the collsion. Price informed defendant he was under arrest and took him to the county jail for booking. Price testified that during the roughly three hours or so that he had contact with defendant between approximately 8:20 p.m. and 11:30 p.m., defendant never asked about the condition of the occupants of the Nissan.

Accident Reconstruction Investigation and Expert Testimony

Redwood City Police Motor Officer Janine O'Gorman, the lead traffic investigator for the accident in question, testified in the prosecution's case-in-chief. She arrived at the scene at 9:30 p.m. O'Gorman first walked around the perimeter of the large debris field and made a visual inspection of the vehicles involved in the collision in order to establish a reference point and map out the scene. Based on the gouge mark on the roadway and the point at which the yaw3 and tire friction marks began, O'Gorman determined that the point of impact was at the intersection of Woodside and Santa Clara. O'Gorman observed yaw marks which began at the point of impact and led straight to defendant's Mercedes. The distance from the point of impact to the Mercedes was 239.9 feet. O'Gorman determined that the Nissan came to rest 60 feet from the point of impact. There was no evidence of prebraking tire friction marks consistent with the Mercedes's antilock braking system, indicating that defendant did not apply his brakes before the collision.

On cross-examination, O'Gorman testified that under California's basic speed law a driver must drive at a speed that is safe under prevailing conditions. O'Gorman regularly patrols the stretch of Woodside Road where the collision occurred. On that stretch, drivers usually exceed the posted speed limit of 35 miles per hour at night when traffic is extremely light. Using a radar gun, O'Gorman clocked the average nighttime driving speed at 40 miles per hour. Police deem that speeds of 50 miles per hour and above are unsafe on that stretch of Woodside Road.

Officer Jincy Pace, a traffic accident investigator with the San Jose Police Department, testified for the prosecution as an expert in the area of collision reconstruction. Based on her review of photos of the collision scene, Officer Gorman's diagram mapping the scene, and forensic mapping of the crush depth on the vehicles, Pace concluded that the operation of defendant's Mercedes at a speed unsafe for conditions was the primary factor in the collision.

To determine the speed of the Mercedes at the point of impact, Pace used a method known as conservation of linear momentum. Using this methodology, Pace first calculated the postimpact speed of the Mercedes and then she applied what she considered a "ludicrous[ly]" low drag factor of 0.3 (the equivalent of slamming brakes on in snow), to account for the fact that the Mercedes was spinning postimpact.4 Pace opined that defendant's postimpact speed was 47 miles per hour using "a low drag factor." If she applied a drag factor of 0.65, more typical for dry pavement, her estimate of defendant's postimpact speed would have been 69 miles per hour. Using the lower postimpact speed estimate of 47 miles per hour, Pace opined that the speed of defendant's Mercedes at impact (preimpact speed) was 67 miles per hour. She estimated that the Nissan's preimpact speed was 12 miles per hour.

The defense relied upon the testimony of Christopher Kauderer, an expert in accident reconstruction, to counter the opinions of Officer Pace. Kauderer testified that he was not permitted to do any destructive testing or examination of defendant's vehicle, i.e., not allowed to take anything apart. As a consequence, he was unable to conduct a mechanical inspection of the car's three major systems, braking, throttle and steering, to see if there was any preexisting mechanical condition and to document any effects of the collision on those systems. Kauderer opted not to use the wholesale "drag factor" analysis employed by Pace because assigning a drag factor to the Mercedes was, in his opinion, too speculative. The drag factor for the Mercedes was "unknown" because there were too many incalculable variables; in particular postimpact driver input, such as whether defendant had his "foot on the accelerator," steered or braked postimpact.

Instead, to calculate the speed of the vehicles at impact, Kauderer used the principle of conservation of momentum.5 Employing this methodology, Kauderer opined that the Mercedes was traveling at 49 to 52 miles per hour and the Nissan was traveling at seven to nine miles per hour at impact. Based on his examination of the scene and the vehicles, human factors in play, as well as forensic mapping and his conservation of momentum analysis, Kauderer opined the primary collision factor was that the driver of the Nissan entered into the roadway and violated the right of way of the driver of the Mercedes, leaving the driver of the Mercedes insufficient reaction time to brake.

In rebuttal, the prosecution called San Jose Police Officer David Johnson as an expert in accident reconstruction because Officer Pace was unavailable to testify. Johnson conducted a visual inspection of defendant's Mercedes and observed that the car's front left tire was wedged against the wheel well. Johnson opined that the position of the wedged left front tire would prevent any postimpact steering by the driver and increase the Mercedes's drag factor. Johnson also disagreed with Kauderer's assumption that the vehicles reached a common separation velocity and opined that a 29-mile-per-hour postimpact speed for the Mercedes was inconsistent with the distance the vehicle traveled after impact. Finally, Johnson opined that the Mercedes's fuel pump would have shut off on impact.

DISCUSSION

A. Fifth Amendment Privilege Against Self-incrimination

Defendant contends that the testimony of Sergeant Bailey and Officer Price regarding his failure to inquire about the well-being of the occupants of the other vehicle involved in the collision was erroneously introduced as substantive evidence of guilt, in violation of his Fifth Amendment privilege against self-incrimination, and that the error was not harmless beyond a reasonable doubt.

We first address respondent's contention that defendant has forfeited his Fifth Amendment claim by failing to raise an objection below on that ground, citing People v. Stewart (2004) 33 Cal.4th 425 [15 Cal.Rptr.3d 656, 93 P.3d 271] (Stewart) and People v. Arias (1996) 13 Cal.4th 92 [51 Cal.Rptr.2d 770, 913 P.2d 980] (Arias).6 "Ordinarily, a criminal defendant who does not challenge an assertedly erroneous ruling of the trial court in that court has forfeited his or her right to raise the claim on appeal . . . [citations]," even if the claim is one of constitutional magnitude. (Sheena K., supra, 40 Cal.4th at pp. 880-881.) "`The purpose of this rule is to encourage parties to bring errors to the attention of the trial court, so that they may be corrected. [Citation.]' [Citations.]" (Id. at p. 881.)

And yet the forfeiture rule is not absolute. "In general, forfeiture of a claim not raised in the trial court by a party has not precluded review of the claim by an appellate court in the exercise of that court's discretion. [Citations.]" (Sheena K., supra, 40 Cal.4th 887, fn. 7.) "Thus, an appellate court may review a forfeited claim—and `[w]hether or not it should do so is entrusted to its discretion.' [Citations.]" (Ibid.) Typically, appellate courts "have engaged in discretionary review only when a forfeited claim involves an important issue of constitutional law or a substantial right. [Citations.]" (Ibid.)

Nevertheless, appellate court discretion to review forfeited claims of constitutional magnitude is circumscribed by the "established rule" that "a forfeited claim of trial court error in admitting or excluding evidence is not subject to discretionary appellate review." (Sheena K., supra, 40 Cal.4th at p. 888, fn. 7; see, e.g., People v. Lewis and Oliver (2006) 39 Cal.4th 970, 1028, fn. 19 [47 Cal.Rptr.3d 467, 140 P.3d 775] [defendants forfeited confrontation clause claim by failing to raise it below].) However, our Supreme Court has recognized a "limited exception" to the established rule "for constitutional claims initially raised on appeal when closely related to claims raised at trial regarding the admission or exclusion of evidence . . . ." (Sheena K., supra, 40 Cal.4th at p. 888, fn. 7.)

Defendant's claim that the prosecution violated his Fifth Amendment privilege against self-incrimination by introducing evidence at trial of his postarrest, pre-Miranda silence as proof of guilt falls within the limited exception sanctioned by our Supreme Court because it is a question of constitutional law initially raised on appeal and closely related to a claim raised at trial.7 Accordingly, we shall exercise our discretion to consider this legal issue on appeal.

(1) Background

Defendant identifies several occasions during trial when police officers testified he did not ask or inquire about the occupants of the Nissan involved in the collision. Defendant asserts that the admission of this testimony violated his Fifth Amendment right to remain silent.8 The first arose during Officer Price's direct examination about his encounter with defendant as defendant sat in the front passenger seat of Gamino's car:

"Prosecutor: At that time did he [(defendant)] ask you any questions? [¶] . . . [¶]

"Price: He asked me if he could leave, go home.

"Prosecutor: What specifically did he say about that?

"Price: He said that he lived only half a block away. He just—he wanted to go home. He asked if it would be okay for him to walk home. [¶] . . . [¶]

"Prosecutor: When he made this request to go home, what was your response?

"Price: I told him no. That obviously the investigation was still ongoing. We needed him to remain at the scene.

"Prosecutor: At this point, when he made his request to go home, had he asked you any questions about the condition of the occupants in the Nissan?

"Price: No."

Later in Price's examination, the prosecutor asked whether, during Price's contact with defendant from about 8:20 p.m. to approximately 11:30 p.m. on the evening in question, defendant ever asked him "about the condition of the occupants of the Nissan." Price answered, "No." The prosecutor also elicited a similar response from Sergeant Bailey when he asked, "So, during any of this time [prior to defendant's arrest at the police station], did the defendant ever ask you about the occupants of the other vehicle?" Bailey replied, "No, he did not."

(2) Analysis

(1) In the seminal case of Miranda v. Arizona, supra, 384 U.S. 436, the high court held that before a person is subjected to custodial interrogation, police must warn the person "that he has a right to remain silent, that any statement he does make may be used as evidence against him, and that he has a right to the presence of an attorney, either retained or appointed. The defendant may waive effectuation of these rights, provided the waiver is made voluntarily, knowingly and intelligently." (Id. at p. 444.) The purpose of the Miranda warnings is to reduce the risk of coerced confessions and safeguard the Fifth Amendment right against self-incrimination. (See Chavez v. Martinez (2003) 538 U.S. 760, 790 [155 L.Ed.2d 984, 123 S.Ct. 1994].) In order to facilitate our analysis of defendant's Fifth Amendment claim, we first consider when defendant was taken into custody, or restrained in a manner that constitutes the functional equivalent of a formal arrest, for Miranda purposes.

(2) Whether an individual is in custody for Miranda purposes is "resolved by an objective standard: Would a reasonable person interpret the restraints used by the police as tantamount to a formal arrest? [Citations.] The totality of the circumstances surrounding an incident must be considered as a whole. [Citation.] Although no one factor is controlling, the following circumstances should be considered: `(1) [W]hether the suspect has been formally arrested; (2) absent formal arrest, the length of the detention; (3) the location; (4) the ratio of officers to suspects; and (5) the demeanor of the officer, including the nature of questioning.' [Citation.]" (People v. Pilster (2006) 138 Cal.App.4th 1395, 1403 [42 Cal.Rptr.3d 301], fn. omitted (Pilster).) A custody determination "presents a mixed question of law and fact. [Citation.] We apply a deferential substantial evidence standard to the trial court's factual findings, but independently determine whether the interrogation was custodial. [Citation.]"9 (Pilster, supra, 138 Cal.App.4th at p. 1403.)

Our custody determination here is guided by the United States Supreme Court's decision in Berkemer v. McCarty (1984) 468 U.S. 420 [82 L.Ed.2d 317, 104 S.Ct. 3138] (Berkemer). In Berkemer, the high court addressed the issue of whether "the roadside questioning of a motorist detained pursuant to a traffic stop constitute[s] custodial interrogation for the purposes of the doctrine enunciated in Miranda." (Id. at p. 423.) The high court acknowledged "that a traffic stop significantly curtails the `freedom of action' of the driver and the passengers, if any, of the detained vehicle," and also that "few motorists would feel free either to disobey a directive to pull over or to leave the scene of a traffic stop without being told they might do so." (Berkemer, supra, 468 U.S. at p. 436.)

However, the Court stated that an "ordinary traffic stop" rarely rises to the functional equivalent of a formal arrest because it is "presumptively temporary and brief" compared to "stationhouse interrogation, which frequently is prolonged." (Berkemer, supra, 468 U.S. at pp. 437-438.) Moreover, "circumstances associated with the typical traffic stop are not such that the motorist feels completely at the mercy of the police" because of the exposure to public view normally attendant in the situation and the fewer police normally involved; "[i]n short, the atmosphere surrounding an ordinary traffic stop is substantially less `police dominated' than that surrounding the kinds of interrogation at issue in Miranda itself . . . ." (Id. at pp. 438-439.) Accordingly, the court concluded that persons temporarily detained pursuant to an ordinary traffic stop "are not `in custody' for the purposes of Miranda." (Berkemer, supra, 468 U.S. at p. 440.)

(3) Nevertheless, the high court cautioned that "[i]f a motorist who has been detained pursuant to a traffic stop thereafter is subjected to treatment that renders him `in custody' for practical purposes, he will be entitled to the full panoply of protections prescribed by Miranda. [Citation.]" (Berkemer, supra, 468 U.S. at p. 440.) Turning to the case before it, the court noted that a short period of time elapsed between the stop and the arrest, and at "no point during that interval was respondent [(motorist)] informed that his detention would not be temporary." (Id. at pp. 441-442.) In addition, the record established that "a single police officer asked respondent a modest number of questions and requested him to perform a simple balancing test at a location visible to passing motorists." Thus, the court concluded that "[t]reatment of this sort cannot be fairly characterized as the functional equivalent of formal arrest." (Id. at p. 442.)

Berkemer controls our analysis, however the facts here compel a different outcome. First, unlike in Berkemer, the stop in this case was not "temporary and brief." (Berkemer, supra, at p. 437.) Rather, defendant was held at the scene for approximately an hour and a half before he was placed into a patrol car and transported to the police station. Moreover, during that timeframe of approximately an hour and a half, the atmosphere surrounding defendant's detention became increasingly coercive. In this regard, after paramedics had examined defendant and police officers had surveyed the accident scene, defendant asked Officer Price if he could walk to his home less than a block away. Price replied, "I told him no. That obviously the investigation was still ongoing. We needed him to remain at the scene." Later, after police denied defendant's request to walk home, Officer Felker removed defendant from the Toyota Camry, where he was seated with his girlfriend and Gamino, and placed him in the back of the patrol car at approximately 9:30 p.m. Defendant was held in the patrol car for another 20 minutes before he was transported from the accident scene at 9:48 p.m. and driven to the police station for further investigation. At no point prior to defendant's transportation from the scene did police tell defendant he was free to leave the accident scene. To the contrary, defendant's request to leave the scene was denied.

Under these increasingly coercive circumstances, where defendant was held for approximately an hour after the collision, was denied permission to leave the scene, and then placed in the rear of a patrol car for another 20 minutes before being transported from the accident scene to the police station for further investigation, we conclude that any reasonable person would interpret those restraints "as tantamount to a formal arrest." (Pilster, supra, 138 Cal.App.4th at p. 1403.) Under the totality of the circumstances here, we find the police restraints placed upon defendant ripened into those "tantamount to a formal arrest" when police transported defendant from the accident scene in a patrol car at 9:48 p.m. Additionally, the record clearly reflects that defendant did not receive Miranda warnings until he was placed under formal arrest much later that evening.10

Having established defendant was in custody for Miranda purposes when he was transported from the accident scene in a patrol car, and that he did not receive Miranda warnings at that point, we now turn to defendant's claim that the prosecutor's references to his postarrest, pre-Miranda silence violated his Fifth Amendment right against self-incrimination. Neither the United States Supreme Court, nor any California court, has directly addressed the issue of whether the government can admit, in its case-in-chief, evidence of a defendant's postarrest, pre-Miranda silence. However, several federal circuit courts have addressed this issue and arrived at conflicting results. Before we discuss the decisions of the federal circuit courts which have addressed this issue and offer our view of the same, we will first outline several key United States Supreme Court decisions which provide the framework for the analysis of the federal circuit decisions and ours.

In Griffin v. California (1965) 380 U.S. 609 [14 L.Ed.2d 106, 85 S.Ct. 1229], the high court held that the Fifth Amendment "forbids either comment by the prosecution on the accused's silence or instructions by the court that such silence is evidence of guilt." (Id. at p. 615.) In reaching this holding, the high court observed that "comment on the refusal to testify is a remnant of the `inquisitorial system of criminal justice [citation] which the Fifth Amendment outlaws. It is a penalty imposed . . . for exercising a constitutional privilege[ and] . . . cuts down on the privilege by making its assertion costly." (Id. at p. 614, fn. omitted.)

Thereafter, in Doyle v. Ohio (1976) 426 U.S. 610 [49 L.Ed.2d 91, 96 S.Ct. 2240] (Doyle), the high court focused its attention on the issue of whether the State could "impeach a defendant's exculpatory story, told for the first time at trial, by cross-examining the defendant about his failure to have told the story after receiving Miranda warnings at the time of his arrest." (Id. at p. 611, fn. omitted.) The court acknowledged "the importance of cross-examination," and expressly noted that the state did not seek to use defendant's silence "as evidence of guilt." (Id. at p. 617.) Nevertheless the court concluded "the Miranda decision compels rejection of the State's position." (Ibid.) Referencing Miranda, the court stated: "The warnings mandated by that case, as a prophylactic means of safeguarding Fifth Amendment rights, [citation], require that a person taken into custody be advised immediately that he has the right to remain silent, that anything he says may be used against him, and that he has a right to retained or appointed counsel before submitting to interrogation. Silence in the wake of these warnings may be nothing more than the arrestee's exercise of these Miranda rights. Thus, every post-arrest silence is insolubly ambiguous because of what the State is required to advise the person arrested. [Citation.] Moreover, while it is true that the Miranda warnings contain no express assurance that silence will carry no penalty, such assurance is implicit to any person who receives the warnings. In such circumstances, it would be fundamentally unfair and a deprivation of due process to allow the arrested person's silence to be used to impeach an explanation subsequently offered at trial." (Doyle, supra, 426 U.S. at pp. 617-618, fn. omitted.) Accordingly, the high court held that "the use for impeachment purposes of petitioners' silence, at the time of arrest and after receiving Miranda warnings, violated the Due Process Clause of the Fourteenth Amendment." (Id. at p. 619.)

Subsequently, in Jenkins v. Anderson (1980) 447 U.S. 231 [65 L.Ed.2d 86, 100 S.Ct. 2124] (Jenkins), the high court clarified the scope of its holding in Doyle. In Jenkins, the defendant was charged with murder after he allegedly stabbed and killed a man. The defendant surrendered himself to police two weeks after the stabbing. At trial, the defendant testified that he stabbed the victim in self-defense. On cross-examination, the prosecution questioned the defendant regarding his failure to offer his self-defense justification prior to turning himself in to police authorities. (Id. at p. 233.) During closing argument, the prosecution reminded the jury the defendant waited two weeks before reporting the crime. (Id. at p. 234.) Before the Supreme Court, the defendant contended the prosecutor's actions, in commenting on his prearrest silence, violated his Fifth Amendment right to remain silent. The court rejected the defendant's contention. First, the court observed that the prosecutor's actions did not impermissibly burden the defendant's Fifth Amendment right, noting the defendant waived "`[t]he immunity from giving testimony. . . by offering himself as a witness.'" (Id. at p. 235.) Second, having chosen to testify, the defendant was "`under an obligation to speak truthfully and accurately.'" (Id. at pp. 237-238.) Third, the Court considered "the legitimacy of the challenged government practice"—the attempted impeachment of a the defendant on cross-examination—noting that once a defendant decides to testify, the "`regard for the function of courts of justice to ascertain the truth becomes relevant ....' [Citation.] [¶] Thus, impeachment follows the defendant's own decision to cast aside his cloak of silence and advances the truthfinding function of the criminal trial." (Id. at p. 238.) Accordingly, the court concluded that when a criminal defendant opts to testify, the Fifth Amendment does not bar use of prearrest silence to impeach the defendant's credibility. (447 U.S. at p. 238.)11

Finally, in Fletcher v. Weir (1982) 455 U.S. 603 [71 L.Ed.2d 49, 102 S.Ct. 1309] (per curiam) (Fletcher), the Supreme Court rejected a habeas corpus petitioner's claim that he was denied due process of law under the Fourteenth Amendment when the prosecutor used his postarrest silence to impeach his testimony at trial. (455 U.S. at p. 603.) In Fletcher, the petitioner allegedly stabbed a man during a brawl. As in Jenkins, the defendant was charged with murder and at trial his defense was that he acted in self-defense. Fletcher testified at trial. On cross-examination, the prosecutor inquired about Fletcher's failure to inform the police, at the time of his arrest, that he acted in self-defense. (Id. at p. 604.) The Fletcher court stated that Doyle was inapposite on the question before it because in Doyle "the government had induced silence by implicitly assuring the defendant [via the Miranda warnings] that his silence would not be used against him." (Id. at p. 606.) "In the absence of the sort of affirmative assurances embodied in the Miranda warnings," the court concluded, "we do not believe that it violates due process of law for a State to permit cross-examination as to postarrest silence when a defendant chooses to take the stand." (Id. at p. 607.)

Federal circuit courts addressing the issue of whether the prosecution may elicit evidence of and comment on a defendant's postarrest, pre-Miranda silence as substantive evidence of guilt have drawn on one or more of the above cited Supreme Court opinions in arriving at conflicting conclusions regarding the admissibility of this evidence. The District of Columbia Circuit addressed the issue in U.S. v. Moore (D.C. Cir. 1997) 322 U.S. App.D.C. 334 [104 F.3d 377] (Moore). In Moore, the defendant remained silent after police stopped the vehicle he was driving (the defendant was also the registered owner of the vehicle), searched the vehicle and found weapons and drugs in the engine compartment. At trial, the prosecutor elicited evidence of the defendant's silence in the face of the discovery of the drugs and weapons via the testimony of the arresting officer. Then, during closing summation, the prosecutor argued that if the defendant did not know "`the stuff was underneath the hood, . . . [he] would at least [have] said, "Well, I didn't know it was there."'" (Moore, supra, 104 F.3d at p. 384.)

Following the defendant's conviction, the Moore court addressed the defendant's claim the prosecutor improperly commented on his postarrest, pre-Miranda silence. The court stated that "[a]lthough in the present case, interrogation per se had not begun, neither Miranda nor any other case suggests that a defendant's protected right to remain silent attaches only upon the commencement of questioning as opposed to custody. While a defendant who chooses to volunteer an unsolicited admission or statement to police before questioning may be held to have waived the protection of that right, the defendant who stands silent must be treated as having asserted it. Prosecutorial comment . . . on a defendant's post-custodial silence unduly burdens that defendant's Fifth Amendment right to remain silent at trial, as it calls a jury's further attention to the fact that he has not arisen to remove whatever taint the pretrial but post-custodial silence may have spread. We therefore think it evident that custody and not interrogation is the triggering mechanism for the right of pretrial silence under Miranda. Any other holding would create an incentive for arresting officers to delay interrogation in order to create an intervening `silence' that could then be used against the defendant." (Moore, supra, 104 F.3d at p. 385.)

Similarly, in U.S. v. Velarde-Gomez (9th Cir. 2001) 269 F.3d 1023 (en banc) (Velarde-Gomez), the Ninth Circuit concluded the admission of evidence of the defendant's postarrest, pre-Miranda silence violated his Fifth Amendment privilege against self-incrimination. In Velarde-Gomez, the defendant was convicted of importation of marijuana and possession of marijuana with intent to distribute after 63 pounds of marijuana were found in the gas tank of the vehicle the defendant was driving when he attempted to cross the border from Mexico into the United States. At trial, the arresting United States Customs agent testified as to the defendant's nonresponsiveness after the defendant was informed the drugs had been discovered in his vehicle: According to the arresting agent, the defendant "`just sat there'" and said nothing. (269 F.3d at p. 1027.)

Addressing the defendant's claim that admission of evidence of his postarrest, pre-Miranda silence violated his Fifth Amendment privilege against self-incrimination, the Velarde-Gomez court noted that whereas "... Miranda warnings are required to reduce the risk that suspects subject to the inherent coercion of custodial interrogation will be compelled to incriminate themselves [citation] ...," the warnings themselves are merely "`a prophylactic means of safeguarding Fifth Amendment rights' [citation]—they are not the genesis of those rights." (Velarde-Gomez, supra, 269 F.3d at pp. 1028-1029, quoting Doyle, supra, 426 U.S. at p. 617.) Therefore, the court reasoned, "once the government places an individual in custody, that individual has a right to remain silent in the face of government questioning, regardless of whether the Miranda warnings are given." (Velarde-Gomez, at p. 1029.) The Velarde-Gomez court continued, "the government may not burden that right by commenting on the defendant's post-arrest silence at trial." (Ibid., citing Griffin v. California, supra, 380 U.S. at p. 614 ["`[c]omment on the refusal to testify is a remnant of the "inquisitorial system of criminal justice," which the Fifth Amendment outlaws'"] and Miranda v. Arizona, supra, 384 U.S. at p. 468, fn. 37 ["`The prosecution may not, therefore, use at trial the fact that [the defendant] stood mute or claimed his privilege in the face of accusation.'"].)

In contrast to the decisions of the District of Columbia and Ninth Circuits, the Eighth Circuit has sanctioned the government's use in its case-in-chief of a defendant's postarrest, pre-Miranda silence as evidence of guilt, finding the admission of such evidence does not violate a defendant's Fifth Amendment rights. (U.S. v. Frazier (8th Cir. 2005) 408 F.3d 1102, 1111 (Frazier).) In Frazier, police stopped a U-Haul truck driven by the defendant. After the defendant gave police permission to search the vehicle, police found boxes filled with pseudoephedrine pills behind two mattresses in the rear of the truck. (Id. at pp. 1106-1107.) At trial, the arresting officer testified that the defendant did not say anything when officers told him he was being arrested for possession of a controlled substance. (Id. at p. 1107.) Following his jury trial conviction, the defendant argued that testimony elicited by the government during its case-in-chief concerning the defendant's postarrest, pre-Miranda silence violated his Fifth Amendment right against self-incrimination. (408 F.3d at p. 1109.)

After reviewing several of the United States Supreme Court authorities that we discussed above, the Frazier court focused on the concurring opinion by Justice Stevens in Jenkins, in which Justice Stevens opined that "the `privilege against compulsory self-incrimination is simply irrelevant to a citizen's decision to remain silent when he is under no official compulsion to speak.'" (Frazier, supra, 408 F.3d at p. 1110, quoting Jenkins, supra, 447 U.S. at p. 241 (conc. opn. of Stevens, J.).) Based on Justice Stevens's concurring opinion in Jenkins, the Frazier court reasoned that the crux of the issue before it was "to determine at what point a defendant is under `official compulsion to speak' because silence in the face of such compulsion constitutes a `statement' for purposes of a Fifth Amendment inquiry." (Frazier, at p. 1110.) The court concluded that the defendant in the case at bar was under no compulsion to speak at the time he maintained his silence. The court observed that although the defendant was under arrest, "there was no governmental action at that point inducing his silence. . . . It is not as if [defendant] refused to answer questions in the face of interrogation." (Id. at p. 1111.) Where a defendant is under no compulsion to speak, the court concluded, the use of postarrest, pre-Miranda silence during the government's case-in-chief does not constitute "an impermissible use of an accused's coerced incriminating `statement.'" (Id. at pp. 1110-1111.)

(4) Having considered the federal circuit court decisions directly addressing this significant issue, as well as United States Supreme Court authority addressing more generally the protections afforded defendants under the Fifth Amendment privilege, we now join the federal circuits holding that the right of pretrial silence under Miranda is triggered by the inherently coercive circumstances attendant to a de facto arrest and therefore the government may not introduce evidence in its case-in-chief of a defendant's silence after arrest, but before Miranda warnings are administered, as substantive evidence of the defendant's guilt. (See, e.g., Moore, supra, 104 F.3d at p. 385 ["custody and not interrogation is the triggering mechanism for the right of pretrial silence under Miranda"].)12 Our holding is coextensive with the constitutional guarantees of the Fifth Amendment. The Fifth Amendment commands that "[n]o person . . . shall be compelled in any criminal case to be a witness against himself . . . ." (U.S. Const., 5th Amend.) (5) This principle is "the essential mainstay of our adversary system" and is fulfilled "only when the person is guaranteed the right `to remain silent unless he chooses to speak in the unfettered exercise of his own will.' [Citation.]" (Miranda v. Arizona, supra, 384 U.S. at p. 460.) As importantly, the Fifth Amendment also prohibits the government from using that silence as inferential evidence of a defendant's guilt. (Miranda, at p. 468, fn. 37 ["The prosecution may not, therefore, use at trial the fact that [the defendant] stood mute or claimed his privilege in the face of accusation."].) Our holding that the right of pretrial silence under Miranda is triggered by the inherently coercive circumstances attendant to a de facto arrest protects these core Fifth Amendment values.

(6) Furthermore, we concur in the Moore court's conclusion that a rule precluding the government from using a defendant's postarrest, pre-Miranda silence as substantive evidence of guilt is compelled by existing high court precedent. As stated in Moore, "[I]t is plain from Griffin and Miranda that the prosecution may not use a defendant's silence in its case-in-chief . . . ." (Moore, supra, 104 F.3d at p. 385.) The Moore court read Supreme Court precedent as allowing only two possible "exception[s] to the bar against the use of silence," namely, use of the defendant's silence against a testifying defendant for impeachment purposes (sanctioned in Jenkins and Fletcher), and use of a defendant's prearrest silence as substantive evidence of guilt (acknowledged as an open question in Jenkins, supra, 447 U.S. at p. 236, fn. 2). (Moore, supra, 104 F.3d at p. 389.) The court stated, "Neither exception applies in this case as Moore did not testify and the record does not support the proposition that the prosecution was referring to pre-arrest silence." (Ibid.) Likewise, neither exception applies in this case because defendant did not testify and the prosecution elicited evidence of defendant's postarrest silence. Thus, as in Moore, we conclude defendant's constitutional rights were violated by the introduction of evidence of his pretrial silence in the prosecution's case-in-chief. (See ibid.)

(7) Moreover, our conclusion on this point finds additional support in the high court's guidance that we should consider the legitimacy of the challenged government practice "[i]n determining whether a constitutional right has been burdened impermissibly." (Jenkins, supra, 447 U.S. at p. 238.) In Jenkins, the high court endorsed the legitimacy of impeaching a testifying defendant with his or her postarrest silence as it "follows the defendant's own decision to cast aside his cloak of silence and advances the truthfinding function of the criminal trial." (Ibid.) Here, by contrast, defendant did not cast aside his cloak of silence but instead exercised his Fifth Amendment right to remain silent and did not testify in his defense. Under these circumstances, no legitimate purpose is served by allowing the prosecution to introduce evidence of defendant's postarrest silence because it does nothing to advance the truthfinding function of the criminal trial. If anything, evidence of a defendant's postarrest silence tends to obfuscate the truthfinding function of the criminal trial: First, its probative value is minimal (see Doyle, supra, 426 U.S. at p. 617 [stating evidence of silence is "insolubly ambiguous because of what the State is required to advise the person arrested"]); second, despite its minimal probative value, the prosecution inevitably seeks to draw highly prejudicial inferences from the defendant's silence; and third, its introduction may impermissibly shift the burden of proof to the defendant in the sense that a defendant must surrender the right against self-incrimination in order to refute the negative inferences inevitably drawn by the prosecution from postarrest silence. Accordingly, we conclude that no legitimate purpose is served by allowing the prosecution to introduce defendant's postarrest silence as substantive evidence of guilt. (Cf. Jenkins, supra, 447 U.S. at p. 238.)

(8) In reaching this conclusion, we respectfully disagree with the rule articulated by the Eighth Circuit that only postarrest, pre-Miranda silence in the face of actual police interrogation is entitled to the privilege. (See Frazier, 408 F.3d at p. 1111 [5th Amend. privilege against self-incrimination does not attach until a person is under a "government-imposed compulsion to speak"].)13 In our view, the Eighth Circuit's rule renders Fifth Amendment protections illusory because it neither accounts for the inherently coercive atmosphere attendant to an arrest nor recognizes the compulsion to speak inherent in allowing the government to comment adversely on a defendant's silence at the time of arrest. Thus, under the rule adopted by the Eighth Circuit, if a defendant does not speak out after arrest but before receiving Miranda warnings, then he or she must either surrender the Fifth Amendment right against self-incrimination at trial or suffer the consequences of allowing the government to articulate how his or her postarrest failure to speak points to guilt. Accordingly, we reject the Eighth Circuit rule because it impermissibly burdens the constitutional guarantees of the Fifth Amendment. (See Moore, supra, 104 F.3d at p. 385 ["Prosecutorial comment ... on a defendant's post-custodial silence unduly burdens that defendant's Fifth Amendment right to remain silent at trial, as it calls a jury's further attention to the fact that he has not arisen to remove whatever taint the pretrial but post-custodial silence may have spread."].)

In sum, defendant was under de facto arrest when he was driven from the scene of the accident in a patrol car and he was not given Miranda warnings at that time. During its case-in-chief, the government elicited testimony from Sergeant Bailey and Officer Price that, subsequent to his arrest, defendant never inquired about the welfare of the occupants of the other vehicle. The government offered this evidence of defendant's postarrest, pre-Miranda silence as substantive evidence of defendant's guilt, in violation of his Fifth Amendment right against self-incrimination. (Velarde-Gomez, supra, 269 F.3d at p. 1028 [testimony regarding defendant's lack of emotional response when informed marijuana found in his vehicle was "tantamount to evidence of silence" in violation of defendant's 5th Amend. rights].)14

(3) Prejudice

The erroneous introduction of evidence of defendant's silence is trial error subject to the harmless error analysis of the standards of Chapman v. California (1967) 386 U.S. 18 [17 L.Ed.2d 705, 87 S.Ct. 824] (Chapman). (See Arizona v. Fulminante (1991) 499 U.S. 279, 310 [113 L.Ed.2d 302, 111 S.Ct. 1246].) The Chapman standard "`requir[es] the beneficiary of a [federal] constitutional error to prove beyond a reasonable doubt that the error complained of did not contribute to the verdict obtained.' [Citation.] `To say that an error did not contribute to the ensuing verdict is ... to find that error unimportant in relation to everything else the jury considered on the issue in question, as revealed in the record.' [Citation.] Thus, the focus is what the jury actually decided and whether the error might have tainted its decision. That is to say, the issue is `whether the ... verdict actually rendered in this trial was surely unattributable to the error.' [Citation.]" (People v. Neal (2003) 31 Cal.4th 63, 86 [1 Cal.Rptr.3d 650, 72 P.3d 280].)

On this record, the People cannot show that the verdict rendered in this case was "surely unattributable to the error." (People v. Neal, supra, 31 Cal.4th at p. 86.) The evidence against defendant in this case, as described above, was essentially in equipoise, and the prosecutor placed great emphasis upon the erroneously admitted evidence in closing argument. (Compare People v. Lewis (2008) 43 Cal.4th 415, 465-466 [75 Cal.Rptr.3d 588, 181 P.3d 947] [any error in admission of codefendant's redacted statement at joint trial was harmless beyond a reasonable doubt in light of "powerful evidence supporting the jury's verdicts ... and the prosecutor's minimal use of [the disputed] statement in the relevant portions of his closing argument"] with People v. Esqueda (1993) 17 Cal.App.4th 1450, 1487 [22 Cal.Rptr.2d 126] [erroneous admission of defendant's statements not harmless beyond a reasonable doubt where other evidence of defendant's involvement in killing was mainly circumstantial and prosecutor heavily relied upon the statements to undermine the defense case].)

For example, a key issue at trial was determining the preimpact speed of defendant's vehicle. There was no dispute defendant was traveling faster than the posted speed limit of 35 miles per hour on Woodside Road. The question, however, was whether defendant acted with gross negligence in driving over the speed limit and whether his conduct displayed an "I don't care attitude"15 and was so reckless that it created a high risk of death or great bodily injury. There were no eyewitnesses to the accident and no physical evidence, mechanical or recorded, which could conclusively determine defendant's speed at impact. Rather, both sides presented the testimony of accident reconstruction experts, and each adopted a different methodology in calculating defendant's speed at impact. The prosecution's evidence established defendant's speed at impact was, at minimum, 67 miles per hour, and possibly much higher. However defendant's expert opined defendant's speed at impact was between 49 and 52 miles per hour, on a stretch of road where drivers routinely exceed the posted speed limit and police deem speeds of up to 50 miles per hour safe under certain conditions. Thus the resolution of defendant's guilt hinged upon the jury's resolution of the conflicting expert testimony.

During closing argument, the prosecution vigorously pressed the jury to find defendant's speed at impact was reliably determined by its expert. The prosecutor argued that defendant's speed, at the time of impact, demonstrated the "I don't care" attitude consistent with establishing gross negligence. After asserting that defendant "barrel[ed] down Woodside at double the speed limit," the prosecutor rhetorically stated, "Why did he not ... at least slow down? ... Because he was grossly negligent. He was driving down that night ... without a care of what was going to happen. I don't care is the attitude that he had." The prosecutor explained to the jury that it could not consider defendant's failure to testify, but "should and can absolutely consider... how he acted the night of the collision. And there's so much evidence about this. And all of it points to one thing; his consciousness of his own guilt." Pressing his theme, the prosecutor added: "The next one I think is particularly offensive, he never, ever asked, hey, how are the people in the other car doing? Not once.... Now you step on somebody's toe ... what is your first thing out of your mouth? Whoops. I'm sorry. I'm not saying that he has to say sorry as an expression of his guilt or as some kind of confession, but simply as an expression of his regret. Look, I'm sorry those people were hurt. [¶] Not once. Do you know how many officers he had contact with that evening? Not a single one said that, hey, the defendant asked me about how those people were doing. Why is that? Because he knew he had done a very, very, very bad thing, and he was scared. [¶] ... And he was obsessed with only one thing, that is, saving his own skin. That's why he said, hey, can I just go home."

Under these circumstances—an emotionally charged case, involving the death of one child and serious injury to another, and hinging on competing theories of accident reconstruction yielding widely different estimates of defendant's speed at the point of impact—the prosecutor's argument urging the jury to consider defendant's failure to ask about the welfare of the occupants of the other vehicle as substantive evidence of his guilt was highly prejudicial. In sum, because the state has failed to demonstrate beyond a reasonable doubt that the erroneous admission of evidence of defendant's postarrest, pre-Miranda silence did not contribute to the jury's guilty verdict, the judgment must be reversed. (See People v. Neal, supra, 31 Cal.4th at p. 86.)

B. Other Issues

Given our conclusion that the violation of defendant's Fifth Amendment rights requires reversal, we need not resolve the other issues raised on appeal, with one exception. For the guidance of the parties in the event the issue is raised upon a retrial (see People v. Neely (1993) 6 Cal.4th 877, 896 [26 Cal.Rptr.2d 189, 864 P.2d 460]), we shall address defendant's contention that the jury instructions on gross vehicular manslaughter (GVM) were legally deficient.

Defendant asserts that the standard of gross negligence defined in the court's GVM instruction is legally indistinguishable from the "wanton disregard for safety" standard defined in the reckless driving instruction. Therefore, according to defendant, the GVM instruction eliminates the requirement that the prosecution prove the predicate offense of reckless driving.16 We disagree.

Gross negligence is defined in the GVM instruction (CALCRIM No. 592) as follows: "Gross negligence involves more than ordinary carelessness, inattention, or mistake in judgment. A person acts with gross negligence when: [¶] 1. He or she acts in a reckless way that creates a high risk of death or great bodily injury; AND, [¶] 2. A reasonable person would have known that acting in that way would create such a risk. [¶] In other words, a person acts with gross negligence when the way he or she acts is so different from how an ordinarily careful person would act in the same situation that his or her act amounts to disregard for human life or indifference to the consequences of that act."

The elements of reckless driving17 (CALCRIM No. 2200) are as follows: "1. The defendant drove a vehicle on a highway; [¶] AND, [¶] 2. The defendant intentionally drove with wanton disregard for the safety of persons or property. [¶] A person acts with wanton disregard for safety when (1) he or she is aware that his or her actions present a substantial and unjustifiable risk of harm, and (2) he [or she] intentionally ignores that risk. The person does not, however, have to intend to cause damage."

(9) Defendant's contention fails because it assumes that "gross negligence" as defined in the GVM instruction is coextensive with the "wanton disregard for the safety of persons or property" as defined in the reckless driving instruction. However, as the court's instructions make clear, "gross negligence" is judged under an objective, reasonable person standard. (People v. Watson (1981) 30 Cal.3d 290, 296 [179 Cal.Rptr. 43, 637 P.2d 279] ["A finding of gross negligence is made by applying an objective test: if a reasonable person in defendant's position would have been aware of the risk involved, then defendant is presumed to have had such an awareness."].) On the other hand, to establish the mental state required to prove reckless driving, the evidence must establish that the defendant acted with a "`wanton disregard for the safety of persons or property'" (People v. Schumacher (1961) 194 Cal.App.2d 335, 339 [14 Cal.Rptr. 924]), where "wantonness" includes the elements of consciousness of one's conduct, intent to do or omit the act in question, realization of the probable injury to another, and reckless disregard of consequences. (Id. at pp. 338-340; see also People v. Dewey (1996) 42 Cal.App.4th 216, 221 [49 Cal.Rptr.2d 537].) Thus, under the court's instructions, if the jury concluded, under the reasonable person standard, that the defendant acted with gross negligence, they were required to make the additional finding that defendant acted with the requisite, subjective mental state required for reckless driving. Therefore, the jury instructions on GVM did not eliminate the predicate offense element of reckless driving and we reject defendant's assertion of instructional error.

DISPOSITION

We realize that the conclusion we reach today will not provide certainty of outcome for any of the parties impacted by the tragic vehicular accident which occurred on the evening of February 19, 2007. However, where, as here, a defendant's right to a fair trial is prejudiced as a result of a violation of constitutional rights, our duty is clear—we are required to reverse the conviction. Accordingly, the judgment is reversed and the matter remanded for further proceedings consistent with this opinion. The petition for habeas corpus is dismissed as moot.

Pollak, Acting P. J., and Siggins, J., concurred.