Anthony George Iron Cloud, Sr. was convicted by a jury of involuntary manslaughter under 18 U.S.C. §§ 1153 and 1112. He appeals the district court's decision to admit into evidence the results of a portable breath test ("PBT") claiming that its admission deprived him of a fair trial. We reverse and remand for a new trial.

At 9:30 p.m. on January 19, 1997, Anthony Iron Cloud gave a friend a ride to his home in the Evergreen housing area of Pine Ridge Reservation. According to Iron Cloud, he had consumed six beers over the course of six hours.2 When Iron Cloud reached the housing area, he saw a pedestrian, Abel Iron Rope, walking along the right-hand side of the road. According to Iron Cloud, he pulled over to the left to avoid the pedestrian. He then turned to look at his passenger and hit Iron Rope. It is undisputed that Iron Cloud never applied his brakes and was driving 15 miles per hour in a 10 mile per hour zone before the accident occurred.

Abel Iron Rope had an extensive history of mental illness and was characterized by his family as a danger to himself and to the community. Iron Rope also had a history of jumping in front of cars. In 1993, he jumped in front of a propane truck on the highway causing the truck to careen into a ditch. Furthermore, a police officer testified that at approximately 4:00 p.m. on January 19, 1997, the day of the accident, Iron Rope ran out directly in front of his patrol car and the officer was barely able to avoid hitting him.

After the accident, Iron Cloud and his friend checked on Iron Rope, who was sitting up and nodded when asked if he was fine. Iron Cloud left the scene of the accident, went home, and asked his wife to call 911.3 The police arrived shortly thereafter. Twenty-five minutes after the accident, Tribal Officer Twiss administered a portable breath test ("PBT") which indicated a blood-alcohol level of .14 percent. Iron Cloud was arrested and approximately one hour after the accident he was given an intoxilyzer breath test which registered his blood-alcohol level as. 11 percent. Five hours after the crash, a blood test was taken and registered .033 percent. Abel Iron Rope subsequently died as a result of the accident.

Iron Cloud was charged with involuntary manslaughter under 18 U.S .C. §§ 1153 and 1112 for operating his motor vehicle in a grossly negligent manner. Iron Cloud filed a motion in limine to exclude the PBT as evidence of anything more than a screening test used to determine probable cause for arrest. The district court overruled the motion without an evidentiary hearing. At trial, the government's witness was allowed to calculate a blood-alcohol level reading based on a hypothetical question which included the PBT and the other tests performed on Iron Cloud. The expert concluded that Iron Cloud's blood-alcohol level at the time of the accident was .13 or .14 percent.4 At the conclusion of the trial, the district court gave a limiting jury instruction which provided that the PBT should not be considered in isolation, but could be considered with the other tests as proof of intoxication. The jury found Iron Cloud guilty and he was sentenced to 21 months imprisonment and three years supervised release. Iron Cloud appeals the admission of the PBT as substantive proof of his intoxication.

In United States v. Black Cloud, 101 F.3d 1258 (8th Cir.1996), this court set forth a two part test to determine when scientific testimony is admissible. First, the district court must "determine whether the testimony is based on reliable scientific technique, and whether it will assist the jury." Black Cloud, 101 F.3d at 1261 (citation omitted). In its determination, the district court should consider the following factors when assessing the reliability of a scientific technique: "(1) whether the technique can be and has been tested; (2) whether the technique has been subjected to peer review and publication; (3) the known or potential rate of error for the technique and the existence and maintenance of standards for controlling the technique's operation; and (4) whether the technique is generally accepted in the scientific community." Id. (citing Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579, 593-95, 113 S. Ct. 2786, 125 L. Ed. 2d 469 (1993)). Second, even if the district court concludes that the expert testimony is admissible, it "may exclude the testimony if the testimony has an unfairly prejudicial effect that substantially outweighs its probative value." Id. (citations omitted).

The district court in this case did not follow either of these steps. The court refused to hold a Daubert hearing to determine the reliability of the test, stating before the jury: "[the] PBT test does not require a Daubert hearing. The PBT test is a test which has been recognized in the scientific community and as such, Daubert is not appropriate." Tr. at 43. Neither did the court analyze whether the test would be unfairly prejudicial. We review a district court's decision to admit evidence for an abuse of discretion. Black Cloud, 101 F.3d at 1261.

By denying Iron Cloud's request for a Daubert hearing on the reliability of the PBT, the judge took the accuracy of the PBTs for granted and he ignored established procedure. Contrary to the court's statements concerning the reliability of the PBT, the PBT has not been established as reliable. PBTs are used in the field for screening purposes. The government's expert witness, Roger Mathison, agreed that the PBT was only a preliminary screening test. Tr. at 197-199. Furthermore, almost every state that has addressed the issue has refused to admit the results of the test for purposes other than probable cause.5 Although the admissibility of evidence is governed by federal standards,6 in the face of this overwhelming case law as to the limited reliability of the PBT, we conclude, without further foundation being laid, that the PBT is not reliable as anything more than a screening test to be used for probable cause.

We are not persuaded by the government's argument that the district court was correct in admitting the results of the PBT test without a Daubert hearing because the technology has been in use for an extended period of time. The mere fact that a test has been used for a long time does not make it reliable. The same argument could be made for polygraph tests, which clearly are not admissible in this circuit. See United States v. Williams, 95 F.3d 723 (8th Cir.1996); Conner v. Auger, 595 F.2d 407 (8th Cir.1979).

Finally, we hold the error was not cured by the judge's limiting jury instruction. Jury Instruction No. 12 stated as follows:

The Court has permitted the introduction of evidence of a portable breath test (PBT) taken of the defendant. You are instructed that a PBT test is not recognized, standing alone, as proof of intoxication. It may be considered, however, together with the tests of the blood, breath (intoxilyzer) and other evidence pointing to the question of whether the defendant was under the influence of alcohol at the time of the event for which the defendant stands charged.

As we have discussed, the PBT should not be used for anything other than probable cause determinations. This instruction simply makes matters worse by instructing the jury that they can consider the PBT as substantive evidence, albeit in conjunction with other evidence.

This court has held that "[e]videntiary rule violations 'which do not affect [a defendant's] constitutional rights are subject to Fed.R.Crim.P. 52(a) harmless error analysis.' " United States v. DeAngelo, 13 F.3d 1228, 1233 (8th Cir.1994). Under this court's interpretation of Fed.R.Crim.P. 52(a), "[a]n error is harmless if the reviewing court, after reviewing the entire record, determines that no substantial rights of the defendant were affected, and that the error did not influence or had only a very slight influence on the verdict." United States v. Wilcox, 50 F.3d 600, 603 (8th Cir.1995) (citation omitted). We will reverse the conviction "only if the jury may have been substantially swayed by improperly-admitted evidence...." Id. (citations omitted).

Iron Cloud was accused of involuntary manslaughter under 18 U.S.C. § 1153 and 1112. The indictment was based upon the allegation that Iron Cloud operated his motor vehicle in a "grossly negligent manner" with actual knowledge that his conduct was a threat to the lives of others or with actual knowledge that would reasonably enable him to foresee the danger to others. The government sought to prove this allegation primarily by showing that Iron Cloud was intoxicated, and heavily relied on the PBT results to do so. We find that the jury may have been improperly influenced by this admitted evidence.

The admission of the PBT results becomes significant considering the government's primary contentions. The government used the PBT results in two ways. First, the government used the results to establish that Iron Cloud was intoxicated. Without the PBT results, Iron Cloud might have successfully disputed the level of his intoxication. The PBT was taken only 25 minutes after the accident and registered a blood-alcohol level of .14 percent, well over the legal limit. Without that level, as the defense expert testified, based on the blood-alcohol reading of Iron Cloud taken some five hours after the accident, Iron Cloud's blood-alcohol level at the time of the accident could have been argued to be between .7 and .8 percent, which is under the legal limit. In giving this opinion, Dr. Robert Looyenga, a chemist who was employed for twenty-five years at South Dakota School of Mines & Technology, assumed the rate of elimination was somewhere between .011 and .015.7

The experts disagreed on the reliability of the intoxilyzer test. The defense counsel challenged the accuracy of both the PBT and the intoxilyzer tests. The intoxilyzer test is measured from the use of the breath, not the blood, so a ratio must be applied to get the results in the form of the blood-alcohol level. The defense contended that this ratio can lead to inaccuracies. The government's expert conceded on cross-examination that the blood test was the most reliable of the three tests and that the intoxilyzer test brought many variables into play.8 Of course, the government disputed the challenges to the intoxilyzer's accuracy.9 It was obviously for the jury to determine the credibility of the conflicting opinions of the two experts. Our primary concern, however, is whether the admission of the PBT test, which showed that Iron Cloud had a much higher alcohol content, bolstered the reliability of the intoxilyzer test and, therefore, influenced the jury in accepting the testimony of the government expert over the testimony of the defense. We cannot be sure that the PBT did not substantially sway the jury in this manner.

The admission of the PBT to prove intoxication is also important considering the circumstances surrounding the accident. It is undisputed that Abel Iron Rope had mental instabilities and had run out in front of cars on at least two previous occasions. In fact, he ran in front of a police officer's car earlier in the afternoon on the day of the accident in question and was nearly hit. Without the PBT to support the theory that Iron Cloud was intoxicated, it is possible the jury could have found that the accident occurred because Abel Iron Rope ran in front of Iron Cloud's car.

Second, the government used the PBT results to undermine the veracity of the defendant. Iron Cloud testified that he drank only six beers that day. According to the government's expert's testimony, however, Iron Cloud would have had to consume at least eleven beers within that time period to have a blood-alcohol level of .13 or .14, the level derived by considering the PBT. Without the PBT results, Iron Cloud's blood-alcohol level could have been as low as .07 or .08 at the time of the accident. As a result, Iron Cloud's testimony would have been consistent with the evidence of the lower blood-alcohol level and his credibility would not have been so easily challenged.

We cannot say that the jury was not greatly influenced by the high blood-alcohol level registered through the PBT shortly after the accident, either as proof of the defendant's intoxication or of his lack of credibility. Therefore, admitting the PBT results was not harmless error.

For the foregoing reasons, the judgment of the district court is reversed and the case is remanded to the district court for a new trial.

CYNTHIA HOLCOMB HALL, Circuit Judge, concurring in part and dissenting.

I agree with the majority that the district court erred by admitting into evidence the PBT results. However, because I believe that the admission of the PBT results had only a slight influence on the jury's verdict, I believe that the district court's error was harmless. Therefore, I dissent.

"This circuit has established that conviction of involuntary manslaughter requires proof that a defendant acted grossly negligent in that he acted with a wanton or reckless disregard for human life, knowing that his conduct was a threat to the lives of others or having knowledge of such circumstances as could enable him to foresee the peril to which his act might subject others." United States v. F.D.L., 836 F.2d 1113, 1118 (8th Cir.1988). The evidence presented at trial showed that Iron Cloud was under the influence of alcohol and marijuana while speeding at night through a residential neighborhood on the wrong side of the road and that, immediately after seeing Able Iron Rope walking along the side of the road, Iron Cloud took his eyes off the road to carry on a conversation with his passenger and ran over Iron Rope.

Independent of the PBT results, the government introduced the results of an intoxilyzer test,10 administered less than one hour after the accident, indicating that Iron Cloud's blood-alcohol content was 0.11. In addition, the government introduced the results of a gas chromatography test11 that, when taken together with the results of the intoxilyzer test, indicated that Iron Cloud's blood alcohol content at the time of the accident was 0.13. Even Iron Cloud introduced evidence showing that his blood alcohol content at the time of the accident was between 0.07 and 0.09. The government's expert testified that Iron Cloud's ability to drive safely would have been significantly impaired at a blood alcohol concentration of 0.08. In addition to the evidence of Iron Cloud's blood alcohol concentration, the government introduced evidence showing that Iron Cloud had been smoking marijuana shortly before the accident. The government's expert testified that the marijuana would have aggravated any impairment from which Iron Cloud was suffering due to the alcohol. Therefore, the jury could have inferred that, even at a blood alcohol content as low as 0.07, Iron Cloud's ability to drive safely was more significantly impaired as a result of the marijuana.

In addition to the empirical evidence of Iron Cloud's impaired ability to drive, the government showed that, instead of staying to help Iron Rope, Iron Cloud fled the scene of the accident and returned home. Although Iron Cloud claims to have told his wife to call 911, he testified that he did not know whether she ever made that call. When the police arrived at Iron Cloud's house, his wife met them at the door and told them Iron Cloud was asleep. However, when Iron Cloud came out of his bedroom, the police noticed that he did not look like he had been sleeping, but instead appeared nervous and intoxicated.12

Under these circumstances, I believe that the evidence shows overwhelmingly that Iron Cloud knew that his actions were a threat to Iron Rope's life, and that despite this knowledge Iron Cloud acted in wanton disregard of Iron Rope's life. Based on the overwhelming evidence demonstrating that Iron Cloud was grossly negligent in running over Iron Rope, I believe that the PBT result had "only a very slight influence on the verdict," and that its admission was therefore harmless error. See United States v. Wilcox, 50 F.3d 600, 603 (8th Cir.1995) (citation omitted).

The majority suggests that Iron Cloud should be absolved of guilt because Iron Rope may have jumped in front of Iron Cloud's truck. I cannot agree because if Iron Cloud had not been drinking and smoking marijuana before driving, and had not been speeding and ignoring the road while he was driving, he could have avoided Iron Rope, even if Iron Rope did jump in front of Iron Cloud's truck.13 Therefore, I believe that Iron Cloud's operation of his truck in this manner was grossly negligent, despite the possibility that Iron Rope jumped in front of Iron Cloud's truck.

Based on the foregoing, I believe that the judgment against Iron Cloud should be affirmed.