OPINION
Defendant Ernest Canipe appeals the district court’s denial of his motion to suppress firearm and ammunition evidence seized from his vehicle and his resulting inculpatory statement. He contends that the evidence, which led to his conditional guilty plea and 192-month prison sentence for felon in possession of a firearm and ammunition contrary to 18 U.S.C. § 922(g)(1), was obtained in violation of his Fourth Amendment rights against unreasonable searches and seizures because his detention was unreasonable, he did not consent to the search of his vehicle, the search exceeded the scope of his alleged consent, and his subsequent statement was tainted by these unconstitutional acts. We disagree and affirm.
I.
Herman Hagie, an investigator with the Washington County (Tennessee) Sheriffs Department, was the sole witness at the evidentiary hearing before a magistrate judge on Canipe’s motion to suppress. Hagie testified that on June 25, 2007, his supervisor told him that Canipe might be in possession of a firearm. 1 Hagie knew Canipe, having previously met him when Canipe was in prison and having later arrested him in an unrelated incident. Hagie was also aware that Canipe had been previously convicted of arson and of attempting to stab a law enforcement officer.
Upon learning that Canipe was expected to check in that day at the probation office *600 in Johnson City but had not yet done so, Hagie attempted to intercept him at the office. Arriving in his unmarked police vehicle, Hagie saw Canipe in the parking lot and called for backup. After observing Canipe leave the parking lot without wearing his seatbelt, a violation of Tennessee law, Hagie performed a traffic stop. The government concedes that Hagie’s motive for the traffic stop was to assess whether Canipe possessed a firearm.
Hagie cited Canipe for failing to wear a seatbelt. The time it took Hagie to write the citation and present it to Canipe was normal, which for that time of day was “[m]aybe even longer” than ten to fifteen minutes. Sometime during this time, Officer Bevins arrived. Shortly thereafter, two other officers arrived, totaling four officers at the scene of the traffic stop.
After Canipe signed the citation, Hagie returned his driver’s license, registration, and proof of insurance. Immediately thereafter, Hagie asked Canipe whether he had “anything” in his vehicle that might be unlawful or about which Hagie needed to know. Canipe responded, “No, he didn’t think so.” Hagie then inquired whether “it would be all right if I looked in” the vehicle or “[y]ou care if I look?” to which Canipe answered that it “wouldn’t be a problem.” After performing a consented frisk, Hagie told Canipe “again that we were going to look through your vehicle, we’re going to go through your vehicle, and [Canipe] never commented.”
While an officer stood with Canipe between the rear of the truck and the front of Hagie’s cruiser — a “short distance” of about ten feet between the two vehicles— Hagie and Officer Bevins searched the truck. Hagie found a closed metal box resembling a tackle box on the front floor of the passenger seat and observed the corner of a second plastic box protruding from beneath the seat. When he moved the seat forward, Hagie discovered that the top of the second box was inscribed with the word “Ruger,” which he knew was a company that manufactured firearms. Hagie opened the Ruger box, observed a handgun inside of it, and placed Canipe under arrest. 2
At the detention center, Canipe was read his Miranda warnings, signed a waiver of his rights, and gave an incriminating statement. He timely appeals the district court’s order adopting the magistrate judge’s recommendation to deny his motion to suppress the evidence seized from his truck, as well as his subsequent inculpatory statement.
II.
We review the district court’s factual findings on a motion to suppress for clear error and its legal conclusions de novo.
United States v. Sanford,
A.
First, Canipe challenges the reasonableness of his continued detention and Investigator Hagie’s request for consent to search his vehicle following the issuance of the citation. He contends that Hagie’s conduct, unaccompanied by evidence of any other criminal act, exceeded what was *601 reasonably related to the circumstances justifying a typical stop for failure to wear a seatbelt. We disagree.
We begin by noting that Canipe does not dispute the lawfulness of the initial stop. Indeed, because Investigator Hagie possessed probable cause to believe that a traffic violation occurred when he observed Canipe not wearing a seatbelt, Hagie’s motivation for making the stop (suspicion of unlawful possession of a firearm) did not undermine its constitutionality.
See Whren v. United States, 517
U.S. 806, 813—19,
Nevertheless, “a seizure that is lawful at its inception can violate the Fourth Amendment if its manner of execution unreasonably infringes interests protected by the Constitution.”
Illinois v. Caballes,
Guiding this inquiry is our en banc holding in
United States v. Erwin,
Investigator Hagie’s continued detention and questioning of Canipe after issuing him the traffic citation were reasonable. Hagie knew Canipe and received reliable information from his sister— through his supervisor — that Canipe was unlawfully possessing a firearm. The stop was not prolonged, Hagie testifying that it was of “normal” duration for a traffic violation at that time of day and much of it was consumed by the purpose of the initial stop, including the need for Hagie to complete the citation and retrieve information from the records dispatch.
See Ellis,
For these reasons, we hold that Investigator Hagie’s brief detention and request for consent to search the truck following the initial stop were reasonable and did not transform the legal traffic stop into an unconstitutional seizure.
B.
Next, Canipe argues that his purported consent to search was invalid. He characterizes his alleged consent as a “mere expression of approval” or “acquiescence” and not the unequivocal, specific, and intelligent consent required to authorize Hagie and Officer Bevins to search his entire vehicle and its contents.
The government bears the burden of demonstrating by a preponderance of the evidence, through “clear and positive testimony,”
United States v. Worley,
Canipe’s contentions lack merit. While defense counsel’s use of the word “acquiesced” in his questioning of Investigator Hagie was an attempt to force a fact witness to adopt counsel’s legal conclusion, such testimony was both incompetent and unpersuasive.
See
Fed.R.Evid. 701 (limiting lay witness opinions and inferences to those based upon the witness’s perception and helpful to a clear understanding of his testimony or a
fact
in issue, not based upon technical or other specialized knowledge within the scope of expert testimony);
Torres v. County of Oakland,
Moreover, Canipe’s comparison of his case with
Worley
is unpersuasive. Worley testified that when law enforcement asked to search his bag, “[he] didn’t feel like [he] could do much of anything,” “[he] couldn’t just walk away,” he did not think that he could just “blow a police officer off,” and he could not say “no” to a police officer.
Worley,
Here, as in
Worley,
the clear error standard requires affirming the district court but, unlike in
Worley,
that outcome is unfavorable to Canipe. In determining whether consent was voluntary, the Supreme Court has deemed relevant both the accused’s characteristics and the details of the interrogation, including the youth of the accused, his lack of education, his low intelligence, the lack of any advice to the accused of his constitutional rights, the length of the detention, the repeated and prolonged nature of the questioning, and the use of physical punishment such as the deprivation of food or sleep.
Schneckloth,
The district court did not clearly err in ruling that Canipe’s consent was voluntary, unequivocal, specific, intelligently given, and uncontaminated by duress or coercion. The duration of the detention and questioning were reasonable. There was no evidence of coercion. Canipe never asked to leave. He responded positively and unambiguously that it “wouldn’t be a problem” for Hagie to search his truck. When Hagie informed Canipe a second time of his intent to search the vehicle, Canipe made no objection. The district court astutely observed that the “[d]efendant has prior criminal convictions, and therefore he is no stranger to the police or the criminal justice system. It defies common sense that he meekly ‘acquiesced’ because he was intimidated by Investigator Hagie.”
We agree and find no clear error in the district court’s ruling that Canipe’s consent was valid.
C.
Finally, Canipe asserts that even if his consent was valid, Investigator Hagie and Officer Bevins unlawfully exceeded its scope. He complains that he was unable to observe the search and only authorized the officers to “look in” his truck, not to move seats or open containers.
“The district court’s determination of whether a search exceeded the scope of consent is a question of fact that we review for clear error.”
United States v. Garrido-Santana,
The district court did not clearly err in ruling that Canipe’s consent to let the officers “[l]ook in” his truck “would be understood by most people to involve a search” of the vehicle, not merely permission to peer through its windows.
See United States v. Gant,
The evidence also does not support Canipe’s contention that he was unable to observe the search. According to Investigator Hagie’s testimony, a third officer stood with Canipe between the rear of the truck and the front of Hagie’s cruiser — a “short distance” of about ten feet between the two vehicles — while Hagie and Officer Bevins searched the truck.
Additionally, Canipe contends that the officers exceeded the scope of his consent when they opened the two closed containers in his truck which stored the handgun and ammunition. The merits of this argument fall between two genre of cases exemplified by
Jimeno
and
State v. Wells,
The
Jimeno
Court distinguished
Wells,
in which the Supreme Court of Florida “held that consent to search the trunk of a car did not include authorization to pry open a locked briefcase found inside the trunk.”
Jimeno,
While the officers did not convey to Canipe the object of their search (distinguishing this case from the permissible consent search in Jimeno), they also did not break or pry open locked containers (distinguishing this ease from the impermissible consent search in Wells). Within this area, we have remarked that it is “ordinarily” true that “general consent [to a search] permits the opening of closed but unlocked containers found in the place as to which consent was given” even “where officers did not tell the suspect the object of their search.”
Gant,
In
United States v. Snow,
[U]nder either the King’s or the Colonists’ English, the term “search” implies something more than a superficial, external examination. It entails “looking through,” “rummaging,” “probing,” “scrutiny,” and “examining internally.” ... [A]n individual who consents to a search of his car should reasonably expect that readily-opened, closed containers discovered inside the car will be opened and examined.
That the defendant did not — and probably could not — know what the officer was looking for does not change our view of his consent. It is self-evident that a police officer seeking general permission to search a vehicle is looking for evidence of illegal activity. It is just as obvious that such evidence might be hidden in closed containers. If the consent to search is entirely open-ended, a reasonable person would have no cause to believe that the search will be limited in some way.
Id.
at 135 (rejecting the defendant’s argument that officers exceeded the scope of his consent when they searched closed bags in his vehicle without first informing him of the purpose of the search).
See also Crain,
*606
When Investigator Hagie asked Canipe whether he had anything in his vehicle that might be unlawful or about which he should know, his questioning placed Canipe on notice that any unlawful item would be the subject of his search. Thereafter, Canipe’s general consent to search the vehicle reasonably included permission to search any container that might have held illegal objects. Significantly, the unlocked box which stored the handgun was inscribed, in plain view, with the name of a familiar firearms manufacturer, thereby rendering its incriminating contents immediately apparent, see
United States v. Campbell,
For these reasons, the district court did not clearly err in ruling that the search was within the scope of Canipe’s consent.
III.
We affirm the district court’s denial of Canipe’s motion to suppress. 3
Notes
. Hagie’s supervisor apparently learned this information from Canipe's half sister.
. The metal tackle box contained ammunition, although it is unclear whether the ammunition was discovered before or after the firearm.
. Our ruling affirming the district court’s denial of Canipe's motion to suppress the firearm and ammunition evidence renders his appeal of the district court’s denial of his subsequent incriminating statement as "fruit of the poisonous tree” moot.
