United States Court of Appeals
                            FOR THE EIGHTH CIRCUIT
           ___________

           No. 04-2289
           ___________

United States of America,               *
                                        *
            Appellant,                  *
                                        *
      v.                                *
                                        *
Mario Alberto Bueno,                    *
                                        *
            Appellee.                   *

           ___________
                                            Appeals from the United States
           No. 04-2338                      District Court for the
           ___________                      Western District of Missouri.

United States of America,              *
                                       *
            Appellee,                  *
                                       *
      v.                               *
                                       *
Mario Alberto Bueno,                   *
                                       *
            Appellant.                 *
                                  ___________

                             Submitted: February 15, 2006
                                Filed: April 17, 2006
                                 ___________

Before WOLLMAN, FAGG, and ARNOLD, Circuit Judges.
                                    ___________

WOLLMAN, Circuit Judge.

      Mario Alberto Bueno pleaded guilty to possessing with intent to distribute five
kilograms or more of powder cocaine. The district court reduced Bueno’s U.S.
Sentencing Guidelines offense level and granted a downward departure from the
guidelines, resulting in a sentence of eighteen months in prison and three years of
supervised release. The government appeals this sentence. Bueno cross-appeals,
arguing that the district court erred in denying his motion to suppress and in quashing
his subpoena duces tecum. We affirm on Bueno’s cross-appeal, and we vacate the
sentence and remand to the district court for resentencing.1

                                          I.

       On January 9, 2001, Corporal Rex Scism and Trooper Kirk Davis (collectively,
officers) of the Missouri State Highway Patrol stopped Bueno for a traffic violation.
The officers had been traveling westbound on Interstate 70 in their patrol car and met
Bueno’s vehicle traveling eastbound on the same highway. Scism testified that he
observed that the vehicle did not have a front license plate and proceeded to stop the
vehicle. Scism approached the vehicle and advised Bueno that he had been stopped
because his vehicle was lacking license plates and because the officers could not
observe a temporary vehicle registration affixed to the vehicle. Scism asked Bueno
for his license and registration. Bueno handed over his license and pointed to the
temporary registration that was affixed to the vehicle’s windshield. The temporary
registration stated that the vehicle belonged to someone other than Bueno.

      After examining the temporary registration, Scism ordered Bueno to exit his
vehicle and wait in the patrol car while the officers checked on the license and

      1
       We also grant Bueno’s motion to supplement the record.

                                         -2-
temporary registration and until they had completed the traffic stop. While Bueno
was waiting in the patrol car, Scism inquired about the owner of the vehicle and
Bueno’s destination. Bueno responded that the vehicle belonged to his brother and
that he was traveling from California to St. Louis, Missouri, where he would meet his
brother and they would purchase some cars to transport back to California.

       After the officers completed checking Bueno’s license and registration, they
documented the warning that they gave to Bueno, returned his license and
registration, and told Bueno to have a safe trip. At that point, Bueno began to exit the
patrol car. Scism testified that he then asked Bueno for consent to search his vehicle
and that Bueno said “Sure, go ahead.” Davis’s testimony corroborates Scism’s
account. Bueno testified that Scism did not ask for consent to search, but instead
grabbed Bueno’s arm, put him on the hood of the vehicle, told him that he was going
to have to search the vehicle, and that Bueno raised his hand and said “Fine.” Upon
searching the vehicle, Scism found a false floor and an access door leading to a
compartment that was not standard for such a vehicle. Because this caused him to
suspect that Bueno was trafficking contraband, he placed Bueno in handcuffs. Scism
then returned to the vehicle and found 76.9 kilograms of cocaine inside the
compartment. He then read Bueno his rights and arrested him for drug trafficking.

      Bueno pleaded guilty to possessing with intent to distribute five kilograms or
more of powder cocaine in violation of 21 U.S.C. §§ 841(a)(1) and (b)(1)(A).
Sentencing took place on April 28, 2004. In accordance with the Presentence
Investigation Report (PSR), the district court applied the 2002 version of the
sentencing guidelines2 and determined that Bueno’s base offense level was thirty-six
and that § 841(b)(1)(A) required a mandatory minimum sentence of ten years in


      2
       Neither party argues on appeal that a different version of the guidelines should
apply in this case. Accordingly, we also apply the 2002 version of the guidelines in
our analysis.

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prison. The district court further determined, however, that Bueno qualified for the
safety valve reduction pursuant to § 5C1.2 of the guidelines. The district court also
concluded that Bueno was entitled to a two-level reduction under § 2D1.1(b)(6) and
a three-level reduction under §§ 3E1.1(a) and (b) for acceptance of responsibility.
This brought Bueno’s adjusted offense level to thirty-one, which provided for a
sentencing range of 108 to 135 months.

       Bueno then argued that he was entitled to a minimal participant reduction under
§ 3B1.2. To buttress his claim that other participants were also involved in the
offense, Bueno offered evidence that the vehicle’s temporary registration was in
another’s name, that personal papers of another were found in the vehicle, and that
Bueno possessed driving directions to Chicago that were in another’s handwriting.
Bueno also explained that Carlos, a man whom he had asked for a loan, gave him the
job of driving the vehicle and that another participant met him at the airport to
provide him with the vehicle. Bueno further explained that he did not fully cooperate
with the police in identifying Carlos because he was afraid that Carlos would retaliate
against him.

       Over the government’s objections, the district court granted Bueno’s request
for a minimal participant reduction. This lowered Bueno’s offense level to thirty
under § 2D1.1. Taking into account the two-level reduction under § 2D1.1(b)(6), the
three-level reduction for acceptance of responsibility, and the four-level reduction for
minimal participation, the district court determined Bueno’s total offense level to be
twenty-one. This corresponded to a sentencing range of thirty-seven to forty-six
months.

      Finally, Bueno argued that he was entitled to a downward departure for
aberrant behavior under § 5K2.20 and family ties and responsibilities under § 5H1.6,
as well as a general departure under § 5K2.0. Bueno argued that a departure was
warranted because this was his first offense, he was under great financial pressure

                                          -4-
when he committed the offense, his wife was suffering from lupus and rheumatoid
arthritis, and because, in his view, this was a case of exceptional circumstances. The
district court granted a downward departure for the reasons stated by Bueno and, as
set forth above, sentenced Bueno to eighteen months in prison and three years of
supervised release. This constituted a fifty-one percent departure from the bottom of
the guidelines range for an offense level of twenty-one and an eighty-three percent
departure from the bottom of the guidelines range for an offense level of thirty-one.

                                         II.

       In United States v. Booker, the Supreme Court struck the statutory provisions
that made sentencing within the U.S. Sentencing Guidelines mandatory. 

(2005). After Booker, a sentencing judge must still determine the proper
guidelines range and determine whether a traditional departure is appropriate under
the guidelines. United States v. Haack, 

, 1002-03 (8th Cir. 2005). These
considerations result in a guidelines sentence. 

Once this guidelines
sentence is determined, the district court must then consider all of the factors
enumerated in 18 U.S.C. § 3553(a) to determine whether to impose the sentence
under the guidelines or a non-guidelines sentence. 

government argues that the district court erred in determining that Bueno
was entitled to a downward adjustment as a minimal participant under § 3B1.2 of the
guidelines. We review the district court’s determination for clear error. See United
States v. Denton, 

, 1114 (8th Cir. 2006). We will affirm a district
court’s determination unless it is not supported by substantial evidence, it resulted
from an erroneous conception of the applicable law, or we firmly believe, after
reviewing the record, that a mistake has been made. United States v. Ramos-Torres,

, 915 (8th Cir. 1999).

                                         -5-
       Section 3B1.2 provides that a defendant’s role in an offense may be reduced
by four levels if the offense involved multiple participants and the defendant was
substantially less culpable than the average participant. U.S.S.G. § 3B1.2, cmt. nn.2
& 3. “The propriety of a downward adjustment is determined by comparing the acts
of each participant in relation to the relevant conduct for which the participant is held
accountable and by measuring each participant’s individual acts and relative
culpability against the elements of the offense.” 

.
Congress intended the downward adjustment for a minimal participant to be used
infrequently, U.S.S.G. § 3B1.2, cmt. n.4, and the defendant has the burden of proving
his eligibility for the decrease in the offense level, United States v. Carrazco, 

, 67 (8th Cir. 1996).

       Bueno offered no evidence of the relative culpabilities of other participants in
the offense and therefore did not carry his burden of proving that he was eligible for
the reduction. Accordingly, the district court’s determination that Bueno was entitled
to a downward adjustment because of his minimal participation in the offense is not
supported by substantial evidence and was clearly erroneous.

                                           B.

       We review for abuse of discretion a district court’s decision to grant a
downward departure from the appropriate guidelines range. United States v. Porter,

, 848 (8th Cir. 2006); United States v. Hawkman, 

, 882 (8th
Cir. 2006). A district court may impose a sentence outside the range if it determines
that the circumstances of the case are so unusual that the case falls outside the
heartland of cases covered by the guidelines. U.S.S.G. § 5K2.0, cmt.; United States
v. Rodriguez, 

, 847-48 (8th Cir. 2005). The district court based its
downward departure on three grounds: (1) aberrant behavior under § 5K2.20, (2)
family ties and responsibilities under § 5H1.6, and (3) a general departure under §
5K2.0. We conclude that the departure was unwarranted.

                                          -6-
       To be entitled for a downward departure due to aberrant behavior under §
5K2.20, the offense must have been a single criminal occurrence or transaction that
was committed without significant planning, was of limited duration, and represented
a marked deviation by the defendant from an otherwise law-abiding life. U.S.S.G. §
5K2.20, cmt. n.1. The offense must have been more than something out of the
defendant’s character; it must have been a spontaneous and thoughtless act. United
States v. Weise, 

, 507 (8th Cir. 1996). Further, a district court may not
grant an aberrant behavior departure if the offense of conviction was a serious drug
trafficking offense, which is any controlled substance offense under Title 21, other
than simple possession. U.S.S.G. § 5K2.20 & cmt. n.1. Bueno’s offense was a
serious drug trafficking offense. See U.S.S.G. § 5K2.20, cmt. n.1. Furthermore,
Bueno’s offense required considerable planning on his part and was carried out over
a number of days. Accordingly, a downward departure on this ground was
unwarranted, and to the extent that the district court relied on this ground in granting
the departure, it abused its discretion.

       Family ties and responsibilities may also be a ground for departure when
extraordinary circumstances are present such that the case lies outside the heartland
of cases covered by the guidelines. See U.S.S.G. § 5H1.6; U.S.S.G. § 5K2.0; see also
United States v. Tobacco, 

, 1151-52 (8th Cir. 2005); United States v.
Harrison, 

, 447 (8th Cir. 1992). This is a disfavored reason, however,
for granting a departure. Koon v. United States, 

, 95 (1996). In United
States v. Haversat, we determined that such a departure was warranted because the
defendant’s wife suffered severe psychiatric problems that were potentially life
threatening and the defendant was an irreplaceable part of her treatment plan. 

, 797 (8th Cir. 1994); see also United States v. Spero, 

, 804-05 (8th
Cir. 2004). In United States v. VanHouten, however, we held that a departure based
on family ties and responsibilities was unwarranted when the defendant failed to
proffer evidence that his mother’s condition was life threatening or that his care was
a necessary part of her medical treatment. 

, 698 (8th Cir. 2002). Bueno

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argues that extraordinary family circumstances are present in his case because his
wife is suffering from lupus and rheumatoid arthritis and he is her primary caregiver.
Bueno’s situation, however, is closer to that in VanHouten than in Haversat. Bueno
has offered little evidence that his wife’s situation is life threatening, and he has failed
to demonstrate that his care is a necessary part of her treatment. Bueno has thus not
established that the circumstances warrant a departure on this ground.

       A district court may also grant a general downward departure pursuant to §
5K2.0 if it determines that a mitigating circumstance, either in kind or to a degree,
was not adequately taken into consideration by the Sentencing Commission in
formulating the guidelines and the case falls outside the heartland of cases covered
by the guidelines. We see nothing in the circumstances that would justify a finding
that this case is other than the all too common situation in which a defendant agrees
to transport drugs for cash.

                                            C.

      Finally, we review the district court’s imposition of an eighteen-month
sentence for reasonableness. See, e.g., United States v. Hadash, 

, 1082-
84 (8th Cir. 2005). After Booker, the sentencing court must consider the factors
enumerated in 18 U.S.C. § 3553(a) in imposing a sentence. See 

within the guidelines range is presumptively reasonable. United States v. Lincoln,

, 717 (8th Cir. 2005). An extraordinary variance from the sentencing
guidelines must be supported by extraordinary circumstances. United States v.
Dalton, 

, 1033 (8th Cir. 2005).

      In the present case, the circumstances are not so extraordinary that they warrant
an eighty-three percent departure from an offense level of thirty-one. An eighteen-
month sentence does not adequately reflect the seriousness of Bueno’s offense, afford
adequate deterrence, or adequately avoid sentencing disparities among similarly

                                            -8-
situated defendants. Accordingly, we conclude that the district court abused its
discretion in granting such a large departure and that the sentence imposed is
unreasonable.

                                           III.

      In his cross-appeal, Bueno contends that the district court erred in denying his
motion to suppress. We examine the factual findings underlying the district court’s
decision for clear error and review de novo the ultimate question of whether the
Fourth Amendment has been violated. United States v. Carter, 

, 714
(8th Cir. 2005).

       First, and underlying each of his Fourth Amendment arguments, Bueno
contends that the district court clearly erred in finding that the officers were credible
witnesses. We generally defer to the district court on issues of credibility, however,
because the district court is in the best position to assess the credibility of witnesses.
See United States v. Walsh, 

, 735 (8th Cir. 2002). Having reviewed the
record, we conclude that the district court did not clearly err in determining that the
officers were credible witnesses and in believing their testimony over Bueno’s
testimony.

       Bueno next argues that because there was no reasonable suspicion for the
traffic stop, all evidence arising out of the stop should be suppressed as fruit of the
poisonous tree. He contends that the stop was based on a mistake of law and
therefore did not provide the requisite reasonable suspicion for the stop. We have
held, however, that neither mistake of law nor mistake of fact renders a traffic stop
illegal so long as the officer’s actions were objectively reasonable in the
circumstances. United States v. Smart, 

, 770 (8th Cir. 2005). We
conclude that the officers’ actions were reasonable under these circumstances. We
credit the district court’s finding that the officers could not see the temporary

                                           -9-
registration affixed to the vehicle’s windshield until after they had stopped the
vehicle. Because a lack of license plates or a temporary registration would have
constituted a violation of state law, the officers had reasonable suspicion to stop the
vehicle.

       Bueno also argues that the officers illegally ordered him out of his vehicle.
Once a vehicle has been stopped for a traffic violation, a police officer may order the
driver out of the vehicle without violating the Fourth Amendment, Pennsylvania v.
Mimms, 

, 108-12 (1977) (per curiam), and thus Bueno’s argument fails.

       Likewise, no Fourth Amendment violation occurred when the officers required
Bueno to remain in the patrol car during the stop. Once officers legitimately stop a
vehicle, they are entitled to conduct an investigation that is reasonably related in
scope to the circumstances that initially justified the stop. United States v.
Bloomfield, 

, 915 (8th Cir. 1994) (en banc). This includes asking the
driver for his license and registration, requesting him to sit in the patrol car, and
inquiring as to the driver’s destination and purpose. 

a defendant is
detained incident to a traffic stop, the officer does not need reasonable suspicion to
continue the detention until the purpose of the traffic stop has been completed. See
United States v. Jones, 

, 924-25 (8th Cir. 2001). We agree with the
district court’s finding that the length of the traffic stop and the detention incident to
the stop was reasonable in relation to the circumstances of the case.

        Bueno further argues that the district court erred in determining that he
voluntarily consented to the search of his vehicle. As recounted above, Scism
testified that he asked Bueno for permission to search his vehicle and that Bueno
responded by stating “Sure, go ahead.” Davis testified to the same effect. We
conclude that the record supports the district court’s finding that Bueno consented to
the search. Bueno also argues that his limited ability to speak and understand English
and his limited experience with police officers made any consent that he may have

                                          -10-
given involuntary. Consent is voluntary if it is “an essentially free and unconstrained
choice by its maker.” Schneckloth v. Bustamonte, 

, 225 (1973). To
determine whether consent has been freely and voluntarily given, we consider the
totality of the circumstances. 

Bueno’s claimed lack of proficiency in the
English language and his limited experience with police officers—at least to the
extent that it may reflect upon his knowledge of protections afforded to suspected
criminals—are relevant factors in determining whether his consent was voluntary.
See United States v. Chaidez, 

, 381 (8th Cir. 1990). The record,
however, reveals that Bueno graduated from a high school in this country, is a long-
term resident, and has three children who primarily speak English. Moreover, the
officers testified that they had no trouble understanding Bueno’s English. Further,
Bueno’s claimed lack of previous experience with police officers does not mandate
a finding that his consent was involuntary. Accordingly, the district court did not
clearly err in finding that Bueno had a sufficient command of the English language
to understand the officer’s request for consent to search his vehicle and that Bueno
voluntarily provided this consent.

                                          IV.

       Finally, Bueno argues that he was deprived of a fair hearing because the district
court erroneously quashed his subpoena duces tecum. Bueno also argues that he was
denied a fair hearing because the court failed to order Scism to explain why he refuses
to use a tape recorder or forms to record defendants’ consents. Bueno fails to cite any
law supporting either of these claims, and we dismiss the latter as meritless.

      We review for abuse of discretion the district court’s decision to quash a
subpoena. United States v. Hardy, 

, 756 (8th Cir. 2000); United States
v. Arditti, 

, 345 (5th Cir. 1992). Federal Rule of Criminal Procedure 17
provides that a subpoena must be issued by a clerk of court, which is signed and
sealed by the clerk. In the present case, because the subpoena was not signed by the

                                         -11-
clerk, it did not comply with the requirements of Rule 17 and was not enforceable.
Moreover, the subpoena did not comply with the substantive requirements of Rule
17. The Supreme Court has made clear that subpoenas duces tecum are not meant to
serve as tools of discovery in criminal cases, but are instead means by which to
expedite the trial by providing a time and place prior to trial for the inspection of
subpoenaed materials. United States v. Nixon, 

, 698-99 (1974). To
require production before trial, then, a moving party must show, among other things,
that the documents are evidentiary and relevant and that the application is made in
good faith and is not intended as a general fishing expedition. 

As the
government points out, Bueno conceded that he did not know the precise nature of
the information sought by the subpoena. The subpoena failed to meet the specificity
requirements of Rule 17, and the district court did not abuse its discretion in quashing
it.

      The district court’s judgment imposing a sentence of eighteen months in prison
and three years of supervised release is vacated, and the case is remanded for
resentencing in accordance with the opinion in Booker, 

. The district
court’s orders denying Bueno’s motion to suppress and granting the government’s
motion to quash Bueno’s subpoena are affirmed.
                       ______________________________




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