Affirmed by published opinion. Chief Judge WILLIAMS wrote the opinion, in which Judge TRAXLER and Judge WOOTEN joined.
OPINION
A jury convicted Kareem B. Farrior of possession with intent to distribute an unspecified quantity of crack cocaine, in violation of 21 U.S.C.A. § 841(a)(1) and (b)(1)(C) (West 1999 & Supp.2008) (Count One), and possession with intent to distribute 50 grams or more of crack cocaine, in violation of 21 U.S.C.A. § 841(a)(1) and (b)(1)(A) (West 1999 & Supp.2008) (Count Two). Because Farrior had two previous convictions for felony drug offenses, the district court sentenced him as a career offender and, under 21 U.S.C.A. § 841(b)(1)(A), imposed a mandatory minimum sentence of life imprisonment. Far-rior appeals his convictions and sentence on numerous grounds and for the reasons that follow, we affirm.
I.
A.
On April 16, 2006, Sergeant Anderson of the Pulaski, Virginia Police Department received a tip that a green car with New York license plates was involved in drug trafficking in the Highland Terrace area in Pulaski. Pulaski police officers located the vehicle in the Highland Terrace area that night, but it was unoccupied.
On April 21, 2006, at approximately 1:15 a.m., Officer Morris of the Pulaski Police Department observed the same green car parked at the end of Maple Street, an area known for drug trafficking. Again, the vehicle was unoccupied. Officer Morris relayed this information to Sergeant Anderson who advised him that this was the same vehicle about which Anderson had received the tip a week earlier.
Thereafter, Officer Morris рarked his patrol cruiser on a nearby street to wait for the driver of the green car to return. Approximately five minutes later, Officer Morris observed the green car pass by him and noticed that the tag light was inoperable on the car. He decided to stop the car because of the inoperable tag light.
Shortly after the stop, Sergeant Anderson learned that Officer Morris had stopped the green car and that the driver was Farrior. Anderson contacted the police dispatcher to obtain Farrior’s criminal history and to request that a canine unit arrive on the scene. Anderson then proceeded to the scene. In response to Sergeant Anderson’s request, Officеr Dowdy, an officer with a drug-sniff dog, also made his way to the scene.
After contacting Sergeant Anderson, Officer Morris requested Farrior’s driver’s license and car registration and returned to his patrol cruiser to check their validity. *215 Both proved to be valid, and Officer Morris returned to Farrior’s car. According to Officer Morris, who had just completed his field training months before the incident, he was not familiar with the process for giving warning tickets for inoperable tag light violations. Consequently, rather than issuing Farrior a traffic citation, Officer Morris returned Farrior’s license and registration and orally warned him that he needed to have his tag light fixed. At this point, Officer Morris told Farrior that he was free to go.
Before Farrior pulled away, however, Officer Morris asked Farrior if he would mind stepping out of the car to talk. Far-rior responded that he was willing to talk from inside his car. Given Farrior’s willingness to speak with him, Officer Morris advised Farrior that the Pulaski Police Department was having problems in the area with drug-related crimes and asked Farrior if he had any drugs or weapons, to which Farrior replied that he did not. Officer Morris then asked Farrior if he could search Farrior’s car, and Farrior agreed. Farrior exited his car and Officer Morris searched Farrior for weapons. Finding no weapons on Farrior’s person, Officer Morris then searched the interior of Farrior’s car.
While Officer Morris was searching the inside of Farrior’s car, Sergeant Anderson arrived on the scene. As Officer Morris concluded his search, finding nothing suspicious, Sergeant Anderson, Officer Morris’s superior, realized that a ticket had not been issued so he instructed Officer Morris to issue Farrior a written warning for the inoperable tag light. Officer Morris once again took Farrior’s license and registration back to his patrol cruiser to write the warning ticket. Officer Morris completed the ticket and was explaining it to Farrior when Officer Dowdy and the drug dog arrived.
Upon arriving, Officer Dowdy was advised by Sergeant Anderson that Farrior had consented to a vehicle search. In response, Dowdy had his drug dog sniff the outside of the car, and it alerted to the presence of drugs in the trunk. Officer Dоwdy then had the dog sniff the inside of the car, and this time it alerted to the console area. Because of this alert, Sergeant Anderson and Officer Dowdy searched the inside of Farrior’s car again, this time noticing that the carpeting and consoles had been altered. At that point, Sergeant Anderson searched Farrior’s trunk and found a black bag with a razor and some white powdery residue.
Sergeant Anderson informed Farrior that the drug dog had indicated the presence of drugs in the car and asked Farrior to remove his boots. Farrior at first refused, but Sergeant Anderson told him that he had no choice but to comply. Accordingly, Farrior kicked off his boots, and inside one of the boots Sergeant Anderson found 5.5 grams of crack cocaine and $2,720.
The officers arrested Farrior and issued him Miranda warnings. Farrior admitted that the cocaine was his, but stated that he had come to Pulaski to buy, not to sell cocaine. Farrior stated that the money in his boot was money that he had earned as a bus driver in Connecticut.
Less than one month later, on May 10, 2006, police officers in Roanoke, responding to a call that someone had been shot, found a wounded Farrior leaning against a car. Farrior, who had been shot three times, was taken to the hospital. As part of their investigation of the shooting, the police located Farrior’s rental car one block from the scene of the shooting and had it towed. On May 12, 2006, after obtaining a search warrant fоr the vehicle, the police searched the vehicle and found 469.5 grams of crack cocaine in the trunk *216 of the car, hidden inside Farrior’s boot. On May 30, 2006, as Farrior was being discharged from the hospital, he was arrested by U.S. Drug Enforcement Administration agents.
B.
On June 1, 2006, a federal grand jury sitting in the Western District of Virginia returned a two-count indictment charging Farrior with possession with intent to distribute an unspecified quantity of crack cocaine and possession with intent to distribute 50 grams or more of crack cocaine.
Before trial, Farrior filed a motion to suppress the evidence seized from the search of his vehicle and his person on April 21, 2006, contending that the seizure violated his Fourth Amendment rights. Following a hearing on thе motion, the district court held that the search did not violate Farrior’s Fourth Amendment rights because (1) his vehicle was legitimately stopped for an inoperable tag light; (2) he voluntarily consented to the search of his car; and (3) the officers had probable cause to search the inside of the car and trunk because a drug dog alerted to the presence of drugs in the vehicle while Officer Morris was issuing Farrior a warning ticket. Accordingly, the district court denied Farrior’s motion to suppress, and the case proceeded to trial.
During jury selection, Farrior objected under
Batson v. Kentucky,
The jury found Farrior guilty of both counts charged in the indictment. In response, Farrior moved for a new trial on the grounds that the Government improperly defined reasonable doubt in its closing argument and improperly invited the jury to place trust in the Government, thus cumulatively lessening the Government’s burden of proof in the case. The district court denied Farrior’s motion.
On June 26, 2006, the Government filed a prior-felony information pursuant to 21 U.S.C.A. § 851 (West 1999 & Supp.2008), giving notice that Farrior was subject to the enhanced penalties set forth in 21 U.S.C.A. § 841(b)(1)(A) due to previous felony drug conviсtions in 1993 and 1996. Thereafter, a probation officer prepared a presentence report (“PSR”). The PSR calculated Farrior’s advisory Guidelines range to be 360 months to life imprisonment, but because Farrior qualified as a career offender under 21 U.S.C.A. § 841(b)(1)(A), a status for which the mandatory minimum sentence is life imprisonment, the PSR adjusted the Guidelines range to recommend the statutory minimum sentence of life imprisonment.
At the sentencing hearing, Farrior objected to the PSR’s conclusion that he qualified as a career offender. The district court disagreed and explained in its statement of reasons that it was imposing a mandatory life sentence pursuant to 21 U.S.C.A. § 841(b)(1)(A). Ultimately, the district court sentenced Farrior to 360 months imprisonment on Count One and to life imprisonment on Count Two, to run concurrently, followed by a 10-year term of supervised release.
Farrior timely appealed his convictions and sentence. We have jurisdiction pursuant to 18 U.S.C.A. § 3742(a) (West 2000) (providing for appellate jurisdiction over a “final sentence” entered by the district court) and 28 U.S.C.A. § 1291 (West 2006) *217 (providing for appellate jurisdiction over “final decisions” of the district court).
II.
On appeal, Farrior challenges: (1) the district court’s denial of his motion to suppress; (2) the denial of his Batson objection to the Government’s strike of the only African American on the venire panel; (3) the denial of his motion for a new trial based on the Government’s closing argument; and (4) variоus aspects of his sentence. We address each argument in turn. 1
A.
We first turn to Farrior’s motion to suppress evidence seized as a result of the search of his vehicle and person on April 21, 2006. On this issue, we review the district court’s factual findings for clear error and its legal conclusions
de novo. United States v. Perkins,
The Fourth Amendment protects the “right of the people to be secure in their persons, houses, papers, and effects against unreasonable searches and sei: zures.” U.S. Const, amend. IV. Following the Supreme Court’s decision in
Terry v. Ohio,
Farrior contends that his Fourth Amendment rights were violated in various ways. He contends that the initial stop should have been terminated at the point when Officer Morris first told him that he was free to go. He asserts that he did not freely consent to the search of his vehicle but was forced to get out of the car. Since no consent was given, he argues that the subsequent search and seizure violated his Fourth Amendment rights because the officers lacked probable cause to continue the stop beyond the scope of the initial encounter. Farrior also contends that even if consent had been given, the duration of time between the purported consent and the time at which Officer Dowdy arrived with the ca *218 nine unit was unreasonable and in violation of his Fourth Amendment rights. This unconstitutional detention, Farrior argues, precipitated the drug-dog sniff that led to the officers’ recovery of all the drug-related evidence.
The district court held that the initial stop was constitutional because Officer Morris possessed (at the least) reasonable suspicion that Farrior was driving with an inoperable tag light, in violation of Virginia Code Ann. § 46.2-1013 (2005); that the search of Farrior’s car did not implicate the Fourth Amendment because Farrior voluntarily consented to the encounter with Officer Morris after the traffic stop was completed; and that the drug-dog sniff was permissible under
Illinois v. Caballes,
Contrary to Farrior’s assertion, the officers did not unreasonably prolong the traffic stop. Under our and other circuits’ precedents, the traffic stop ended once Officer Morris returned his license and registration, orally warned him to fix his tag light, and told him that he was free to go.
See, e.g., United States v. Singh,
The Supreme Court has made it very clear that a “seizure does not occur simply because a police officer approaches an individual and asks a few questions.”
Florida v. Bostick,
Here, Officer Morris asked Farrior a few questions after ending the traffic stop, and Farrior voluntarily responded to the questions in what appears from the record to have been a completely cоnsensual exchange.
See United States v. Weaver,
The facts of the encounter between Officer Morris and Farrior also confirm that Farrior voluntarily consented to the search of his vehicle. Whether consent is voluntary is a factual determination made by examining the totality of the circumstances,
Schneckloth v. Bustamonte,
We have recognized that when the lower court “bases a finding of consent on the oral testimony at a suppression hearing, the clearly erroneous standard is particularly strong since the [court] hаd the opportunity to observe the demeanor of the witnesses.”
Lattimore,
Having determined that Farrior validly consented to the search of his car, we next consider whether the timing and sequence of the events surrounding Officer Morris’s issuance of a warning ticket to Farrior violated the Fourth Amendment. As recounted above, after Officer Morris finished his search of Farrior’s vehicle, Sergeant Anderson instructed Officer Morris to issue Farrior a written warning for the inoperable tag light. Based on Officer Morris’s testimony, the district court found that Officer Morris had just completed his field training months before the traffic stop. At field training, Officer Morris was trained to issue summonses in situations like these, but he did not like to give summonses because they required the defendant to appear in court for a minor offense. At the time of the traffic stop, Officer Morris did not know how to issue a warning ticket. Given this testimony, the district court found that there was no “attempt at subterfuge or stalling on the part of the officers” and that the additional time required to take Farrior’s license and registration and write the ticket was minimal. (J.A. 62.) Based on these findings, the district court concluded that “despite being *220 unusual in sequence, there is nothing in these events that impinges the defendant’s constitutionаl rights.” (J.A. 62.) We agree.
“As is obvious from the constitutional text, the central inquiry under the Fourth Amendment is reasonableness, for ‘what the Constitution forbids is not all searches and seizures, but unreasonable searches and seizures.’ ”
United States v. McCoy,
We also agree with the district court that there was “nothing in the timing or conduct of the canine search [which] violated [Farrior’s] Fourth Amendment rights.” (J.A. 63.) Here, the drug sniff— which, as noted above, does not constitute a “search” under the Fourth Amendment,
Place,
Moreover, even if were inclined to accept Farrior’s argument that to perform the first drug-dog sniff, which required a seizure of Farrior’s vehicle,
Foreman,
B.
Having determined that Farri- or’s Fourth Amendment rights were not violated, we next turn to consider Farrior’s contention that the district court erred in rejecting his
Batson
challenge. “A finding by the [trial] court concerning whether a peremptory challenge was exercised for a racially discriminatory reason is given great deference by this court; we review that finding only for clear error.”
Jones v. Plaster,
When making a
Batson
challenge, the defendant must first make a
prima facie
showing of purposeful discrimination.
See United States v. Malindez,
Farrior, who is African American, argues that the Governmеnt’s use of a peremptory strike to exclude the only African American member of the venire panel violated
Batson.
To make out a
prima facie
case under
Batson,
Farrior had to raise at least an inference that the Government struck the potential juror based on her race.
See Batson,
Because the Government provided race-neutral explanations for the challenged strike, the burden shifted to Farrior to prove that the explanations given were pretext for discrimination,
see Batson,
*222 C.
Farrior also contends that the district court erred by denying his motion for a new trial. He argues that the district court should have granted his motion because the Government improperly defined reasonable doubt in its closing argument and improperly invited the jury to place trust in the Government, thus cumulatively lessening the Government’s burden of proof in the case. Farrior’s arguments focus on several statements made during closing arguments. During its closing argument, the Government discussed the importance of trust in the process of making an argument, referring to its opening statements as promises of evidence and asking the jury to judge whether the promises were kept. Additionally, the Government made the following statements regarding the nature of the Government’s burden:
... I want to mention one thing about one of my burdens, my burden beyond a reasonable doubt. You have heard the judge talk about that a couple of times. You have heard me mention it in my opening statement.
Well, what is a reasonable doubt? Because there’s some misconception about what that is. I’ll tell you what it is not. It is not beyond all doubt. It is not beyond every doubt. It is not beyond each and every single doubt. It is beyond a reasonable doubt, because nothing is a hundred percent certain, except for a few things: death and taxes.
So that’s why the law attaches a reason. Well, what is reason? You are going to hear a jury instruction from the judge defining what reasonable doubt is. 3 And a reason is based on common sense. And you will hear that. It is based on common sense.
If you recall, yesterday, when we were selecting you all as jurors, okay, I don’t recall anybody asking you, “can you leave your common sense at the door for a couple of days and just listen to what I tell you, but don’t use your life experiences?” No. I mean, to the contrary, we want you to use your life experiences. We want you to use your common sense.
So when you evaluate the evidence, you evaluate the testimony, you can ask yourself: Does that make sense? Would I do that? Does that make sense? Does that story make sense?
(J.A. 289-90.) At two points following this explanation, the Government stаted that there was “no other reasonable explanation” for Farrior’s behavior. (J.A. at 290.)
Farrior contends that while each of these statements in isolation may not be sufficient to warrant a new trial, their cumulative effect was such that the jury was given a false impression of the Government’s burden of proof and its duty to weigh the Government’s evidence. Far-rior further argues that the Government’s statements on reasonable doubt constituted an impermissible definition of the Government’s burden in violation of our admonition in
United States v. Adkins,
*223
We find Farrior’s arguments unpersuasive. Of course, remarks made during closing arguments can be sufficient to warrant a new trial if they were improper and prejudicially affected the defendant’s substantial rights.
United States v. Chorman,
Here, like the statements in Adkins and Williams, the Government’s statements only provided general guidance to the jury and did not undermine the jurors’ lay understandings of the term reasonable doubt. Moreover, under plain error review we can in nowise say that any purported error in the Government’s statements was plain, let alone that such error affected Farrior’s substantial rights. Accordingly, we find no reversible error in the Government’s statements to the jury. 5
D.
Finally, we turn to Farrior’s various arguments that the district cоurt erred in sentencing him to life imprisonment.
1.
First, Farrior contends that the district court erred in considering his 1993 conviction as a predicate conviction for purposes of sentencing him as a career offender. He argues that the certified, signed copy of his 1993 conviction relied on by the district court is constitutionally deficient under
Shepard v. United States,
We review the district court’s factual findings for clear error and its classification of Farrior as a career offender
de novo. United States v. Johnson,
2.
Farrior also argues that his sentence was excessive and unreasonable. Under
Gall v. United States,
— U.S. -,
*225 III.
For the foregoing reasons, Farrior’s convictions and sentence are
AFFIRMED.
Notes
. In addition to these arguments, Farrior also argues that there was insufficient evidence for the jury to find that he had intent to distribute crack cocaine; that he should have been granted credit for acceptance of responsibility; and that the district court erred by not declaring a mistrial because after the jury was dismissed, it was noticed that an incorrect verdict form was used, after which the jury completed the proper verdict form. Farrior contends that the jury's finding after it had been discharged is a violation of the Double Jeopardy Clause. Based on our careful review of the record, we conclude that these arguments are without merit.
. Farrior argues that the Supreme Court’s recent decision in
Snyder v. Louisiana,
- U.S. -,
. It should be noted that no such jury instruction was given by the district court.
. Under the plain error standard of review, to establish our authority to notice an error not preserved by a timely objection, a defendant
*223
must demonstrate (1) that an error occurred, (2) that the error was plain, and (3) that it affected his substantial rights. If the defendant satisfies these threshold requirements, correction of the error is within our discretion, which is “appropriately exercised only when failure to do so would result in a miscarriage of justice, such as when the defendant is actually innocent or the error seriously affect[s] the fairness, integrity or public reputation of judicial proceedings.”
United States v. Promise,
. Indeed, the jury was specifically instructed by the district court that it was not to consider the arguments made by the attorneys as evidence in determining guilt or as statements of the law to be applied in the case.
. Farrior also suggests that the district court erred by not giving him an adequate opportunity under 21 U.S.C.A. § 851 (West 1999 & Supp.2008) to contest the Government’s contention that he was subject to the career offender enhancement under 21 U.S.C.A. § 841(b)(1)(A) (West 1999 & Supp.2008). He bases this contention on the fact that the district court spent most of its time at the sentencing hearing discussing U.S. Sentencing Guidelines Manual § 4B1.1 (2006), the career-offender guideline, and not the enhancement under the statute. To be sure, § 851 "was enacted to insure that defendants are given reasonable notice and opportunity to be heard, which includes the opportunity to contest the evidence or challenge a prior conviction if the defendant might be subject to a greater sentence than would otherwise be imposed.” United States v. Jackson, 121 F.3d 316, 319 (7th Cir.1997). Here, it is clear that, even though the district court couched its discussion of Farrior’s predicate convictions in terms of the Guidelines enhancement, Far-rior was given sufficient opportunity to challenge the predicate nature of his 1993 conviction. Indeed, the predicate status of the 1993 conviction was one of the focal points of the sentencing hearing.
. Section 841(b)(1)(A) provides, in pertinent part:
If any person commits a violation of this subparagraph ... after two or more prior convictions for a felony drug offense have become final, such person shall be sentenced to a mandatory term of life imprisonment.
21 U.S.C.A. § 841(b)(1)(A).
. Finally, Farrior urges us to remand his case for re-sentencing in the wake of Amendment 706 to the Guidelines, which lowered the base offense level for drug offenses involving crack cocaine. See U.S. Sentencing Guidelines Manual § 2D1.1 (Nov. 1, 2007); U.S.S.G. Suрp. to App’x C, Amend. 706. Farrior was sentenced on April 24, 2007, prior to the November 1, 2007 effective date of Amendment 706. Amendment 706, however, has been made retroactive, effective March 3, 2008. See U.S.S.G. § 1B1.10(c) (Mar. 3, 2008).
*225
Although Amendment 706 has been made retroactive, after the briefs in this case were filed, we expressly held in another case that it is "for the district court to first assess whether and to what extent [a defendant's] sentence may be thereby affected, and [the district] court is entitled to address this issue either sua sponte or in response to a motion by [the defendant] or the Bureau of Prisons.”
United States v. Brewer,