On March 24, 1989, defendant was arrested and charged with possession with intent to distribute cocaine under 21 U.S.C. §§ 841(a)(1) and (b)(1)(B)(ii) (1988). On November 15, 1989, the United States District Court for the District of Wyoming ordered suppressed certain evidence critical to the government’s case against defendant. United States v. Ibarra, 725 F.Supp. 1195 (D.Wyo.1989). The government subsequently filed a motion for reconsideration, which the district court rejected on January 3, 1990. United States v. Ibarra, 731 F.Supp. 1037 (D.Wyo.1990). The government then appealed the suppression order to this court. We rejected the government’s appeal, holding that the thirty-day period in which to timely file an appeal began running on the date of the district court’s original order rather than on the date the district court denied the government’s motion for reconsideration. United States v. Ibarra, 920 F.2d 702 (10th Cir.1990), vacated, — U.S. —, 112 S.Ct. 4, 116 L.Ed.2d 1 (1991). Because more than thirty days had elapsed between the filing of the original order and the government’s appeal, we dismissed the appeal. Id. The government appealed that dismissal to the United States Supreme Court, which vacated our decision. United States v. Ibarra, — U.S. -, 112 S.Ct. 4, 116 L.Ed.2d 1 (1991). We therefore now proceed to consider the merits of the government’s earlier appeal to this court.

I.

On March 24, 1989, defendant and a companion were travelling east on Interstate 80 through Wyoming at a lawful rate of speed in a white 1981 Oldsmobile Cutlass with California license plates. During this time, Wyoming Highway Patrolman Scott Mahaffey observed that defendant appeared to be driving at a slower speed than other traffic and weaving within his marked lane. Suspecting that defendant may have been intoxicated, Officer Mahaf-fey followed the vehicle for approximately five miles. While following the vehicle, Officer Mahaffey saw it pass two other vehicles without signaling. Officer Mahaf-fey also observed defendant’s vehicle cut in front of another vehicle. After noticing further intermittent weaving, Officer Ma-haffey then stopped the vehicle to determine whether the defendant was intoxicated.

Officer Mahaffey approached the driver’s side of the vehicle and asked defendant for his driver’s license, which defendant promptly produced. When Officer Mahaf-fey informed defendant that he had stopped him for failing to signal prior to making lane changes, defendant responded[*1407] that he thought he had signaled, but perhaps he had not. Although Officer Mahaf-fey stated that he had stopped defendant for suspicion of driving under the influence of alcohol, he failed to pursue an investigation of this possible offense other than by conducting a cursory examination of defendant’s appearance and behavior.

Officer Mahaffey then returned to his patrol car to issue a warning ticket to defendant and to run a check on defendant’s driver’s license. This check revealed that defendant’s license had expired. Using his loudspeaker, Officer Mahaffey requested that defendant bring his vehicle registration to the patrol car. When defendant complied, Officer Mahaffey told defendant about the expired license and wrote a citation which required defendant to post a $220 appearance bond in order to avoid immediate arrest. Defendant returned to his vehicle and produced the required bond money.

After receiving the money for the bond, Officer Mahaffey told defendant that the ownership of the vehicle was in doubt because the registration and ownership certificate bore the name of Charles J. Petrocchi. Defendant explained that he had recently purchased the vehicle from Mr. Petrocchi. Officer Mahaffey then asked his dispatcher to try to contact Mr. Petrocchi to determine whether the vehicle in fact belonged to defendant. Meanwhile, a second Wyoming highway patrol officer arrived at the scene and sat in the back seat of Officer Mahaf-fey’s patrol car.

Defendant then told Officer Mahaffey that he had only $40 remaining with which to travel to Chicago. Officer Mahaffey asked defendant the reason for his travel to Chicago. Defendant responded that he intended to visit some friends there. He later changed his story, however, by stating that he actually was moving to Chicago. Because Officer Mahaffey had seen only a few possessions in defendant’s vehicle, he became suspicious of defendant’s story. He asked defendant whether the vehicle contained any weapons, large amounts of money, or any controlled substances. Defendant answered “no.” Officer Mahaffey then asked whether he could look at the contents of the vehicle. Defendant consented. The officers and defendant got out of the patrol car and approached defendant’s vehicle. Officer Ma-haffey asked if he could look in the trunk. Without verbally responding, defendant opened the trunk. The trunk contained several nylon bags. Without asking whether he could search the bags, Officer Mahaffey opened them but discovered nothing unusual. Officer Mahaffey then searched the passenger compartment while the other officer, Greg Leazenby, continued to search the trunk. The search of the vehicle revealed nothing unusual or illegal. Defendant then shut his trunk.

Officer Mahaffey then informed the passenger in the vehicle that because defendant could not drive without a valid license, she would need to drive the car provided she could produce a valid license. Her license, however, turned out also to be expired. Then, without consulting defendant, Officer Mahaffey contacted a private wrecker to tow defendant’s vehicle to Laramie, Wyoming, which was a short distance away. Officer Mahaffey told defendant that his vehicle would be released when defendant could produce a licensed driver to operate the vehicle.

The officers then drove defendant and his passenger to a Western Union station where they could wire for extra money and find a licensed driver. During this trip, Officer Mahaffey spoke with the wife of Mr. Petrocchi, who informed him that Mr. Petrocchi had in fact sold the vehicle to defendant several weeks earlier. Officer Mahaffey also learned at that time that defendant had no liability insurance for the vehicle.

After dropping off defendant and his passenger at the Western Union station, the officers went to Warren’s towing, which had towed defendant’s vehicle. There they renewed their search of the vehicle. The officers believed that they had defendant’s continuing consent to search the vehicle despite their failure to ask defendant whether that in fact was the case. During the search, the officers re[*1408] moved the nylon bags from, the trunk and lined them up on the ground next to the vehicle. This is a typical procedure followed when conducting an official inventory of an impounded vehicle. After removing those items, the officers discovered a plastic bag behind the spare tire. This bag was removed from the vehicle. It was found to contain several clear plastic gloves and a large package wrapped with duct tape. Through a cut in the tape Officer Mahaffey saw a white powdery substance which turned out to be cocaine. He then returned to the Western Union station and arrested defendant. A federal grand jury later indicted defendant for possession of cocaine with intent to distribute in violation of 21 U.S.C. §§ 841(a)(1) and 841(b)(1)(B)(ii).

The primary issues raised on appeal are 1) whether the impoundment of defendant’s vehicle was reasonable under the Fourth Amendment; 2) whether the suppressed evidence would have inevitably been discovered; and 3) whether the second search of defendant’s vehicle was proper under a theory of continuing consent.^[2]

II.

The Fourth Amendment protects individuals and their property from unreasonable searches and seizures by the government. United States v. Place, 462 U.S. 696, 700, 103 S.Ct. 2637, 2641, 77 L.Ed.2d 110 (1983). “When a search and seizure is challenged as violative of the Fourth Amendment, the burden is on the government to prove its validity.” United States v. Mendenhall, 446 U.S. 544, 550, 100 S.Ct. 1870, 1875, 64 L.Ed.2d 497 (1980); United States v. Carreon, 872 F.2d 1436, 1441 (10th Cir.1989).

Defendant contends that the impoundment of his automobile was an unlawful seizure, and therefore any evidence found during a subsequent search of the seized vehicle should be suppressed as “fruit of a poisonous tree.” See Wong Sun v. United States, 371 U.S. 471, 484, 83 S.Ct. 407, 415, 9 L.Ed.2d 441 (1963). Following an evidentiary hearing on defendant’s motion to suppress, the district court held that Officer Mahaffey’s impoundment of defendant’s vehicle was not authorized by law and therefore violated the Fourth Amendment. As a result, the district court granted defendant’s motion to suppress. We must affirm this ruling unless we find it to be clearly erroneous. United States v. Rinke, 778 F.2d 581, 589 (10th Cir.1985) (“[A] district court’s ruling on a motion to suppress will be affirmed unless shown to be clearly erroneous.”).

Wyoming law provides that a police officer may move an illegally stopped or abandoned vehicle from a public roadway to a place of safety.^[3] Under Wyoming law, police officers may only remove an illegally stopped vehicle if it obstructs the normal movement of traffic, Wyo.Stat.Ann. § 31-5-508(b), or under the following circumstances:

(i) Report has been made that the vehicle has been stolen or taken without the consent of the owner;

(ii) The person in charge of the vehicle is unable to provide for its custody or removal; or

(iii) When the person driving or in control of the vehicle is arrested for an alleged offense for which the officer is required by law to take the person arrested before a proper judge without unnecessary delay.

Wyo.Stat.Ann. § 31-5-508(c). In addition, the Supreme Court has ruled that police officers may impound a vehicle which threatens public safety. South Dakota v. Opperman, 428 U.S. 364, 369, 96 S.Ct. 3092, 3097, 49 L.Ed.2d 1000 (1976) (plurality opinion).

[*1409] Therefore, the government bears the burden of showing that its seizure of defendant’s vehicle satisfies one of these standards. The district court held that the government failed to carry this burden. Specifically, the district court found that defendant’s vehicle did not obstruct the normal flow of traffic in violation of § 31-5-508(b). This finding is supported by the undisputed fact that the police officers at the scene did not request defendant to move his car while the officers waited forty-five minutes for the wrecker to arrive.

The district court also found that defendant’s situation did not justify removal of the vehicle under Wyoming statute § 31-5-508(c) for the following reasons: 1) there was no report that the vehicle had been stolen; 2) the person in charge of the vehicle was able to provide for the custody of the vehicle but was never given the opportunity to do so by Officer Mahaffey; and 3) defendant was not under arrest at the time Officer Mahaffey elected to have the vehicle removed. Id.4

Such factual findings can only be reversed by this court if we find them to be clearly erroneous. United States v. Guglielmo, 834 F.2d 866, 868 (10th Cir.1987); United States v. Cooper, 733 F.2d 1360, 1364 (10th Cir.1984). Moreover, the evidence on appeal must be viewed in the light most favorable to the district court findings. Guglielmo, 834 F.2d at 868; United States v. Lopez, 777 F.2d 543 (10th Cir.1985). We hold that the district court’s factual findings regarding the lack of justification for the impoundment pursuant to sections 31—5—508(b) or 31-5-508(c) are not clearly erroneous.

Although the district court’s factual findings are subject to a “clearly erroneous” standard of review, the ultimate determination of the reasonableness of Officer Mahaffey’s seizure and search is a question of law to be reviewed by this court de novo. United States v. Pena, 920 F.2d 1509, 1513-14 (10th Cir.1990).

The government argues that Officer Ma-haffey’s decision to impound defendant’s vehicle was reasonable because defendant could not provide for the custody or removal of his vehicle and therefore Officer Ma-haffey was authorized to remove the vehicle to a place of public safety under Wyoming statute § 31-5-508(c). Appellant’s Reply Brief at 10. Because we hold that the district court’s finding that defendant was in fact able to provide for the removal and custody of his vehicle was not clearly erroneous, we conclude that Officer Mahaf-fey’s decision to impound the vehicle was made without proper authority under Wyoming law. Therefore his decision was not reasonable and in conformance with the Fourth Amendment unless justified under Opperman.

Although Officer Mahaffey did not conform to Wyoming law when seizing defendant’s vehicle, the much closer question in this case is whether reasons of public safety dictated that Officer Mahaffey impound the car as allowed under Opperman, 428 U.S. 364, 369, 96 S.Ct. 3092, 3097. Clearly, police officers must have a certain amount of discretion in determining what threatens public safety. Indeed, Officer Mahaffey testified that he elected to have the car impounded because it posed a safety hazard. The district court found, however, that this testimony lacked credibility, and we must rely on that finding unless clearly erroneous. United States v. Axselle, 604 F.2d 1330 (10th Cir.1979) (credibility of witnesses, weight to be given evidence, and drawing of inferences are for the trial judge). It appears that if the position of[*1410] the vehicle would have been a true threat to public safety, the officers would have moved the vehicle to the side of the road while waiting for the tow truck to arrive. Furthermore, the potential existed that the real reason the officers wished to remove the vehicle to a more secure location was to conduct a more intensive investigatory search. See infra note 7. We thus cannot hold that the district court’s finding was clearly erroneous.^[5]

We conclude that the government failed to carry its burden of showing that the impoundment of defendant’s vehicle was authorized by Wyoming law or Opperman. Therefore, we affirm the district court’s holding that the seizure of defendant’s vehicle was unreasonable.

III.

The government argues that even if the second search of the vehicle was unlawful, the evidence found during the second search should nevertheless be admissible because it would have been inevitably discovered during a routine inventory of the vehicle’s contents. Nix v. Williams, 467 U.S. 431, 104 S.Ct. 2501, 81 L.Ed.2d 377 (1984), established that the inevitability of discovering evidence by lawful means removes the taint from evidence first discovered through unlawful means. An inventory search is a well-defined exception to the warrant requirement of the Fourth Amendment. Colorado v. Bertine, 479 U.S. 367, 371, 107 S.Ct. 738, 741, 93 L.Ed.2d 739 (1987); Opperman, 428 U.S. at 372, 96 S.Ct. at 3098. Consequently, if evidence seized unlawfully would have been inevitably discovered in a subsequent inventory search, such evidence would be admissible.

In this case, however, no inventory of the contents of defendant’s vehicle could have been conducted but for the unlawful im-poundment of the vehicle. Thus, the government cannot claim that the evidence eventually seized during the second search would have been inevitably discovered.^[6] Therefore, the inevitable discovery doctrine cannot operate to remove the taint of the Fourth Amendment violation in this case. We decline to unnecessarily address other issues relevant to considering the inevitable discovery doctrine’s application to this case.^[7]

[*1411] IV.

Although we hold today that defendant’s vehicle was unlawfully seized and subsequently searched, it is well-established that certain exceptions to the exclusionary rule may render evidence discovered pursuant to an unlawful seizure nevertheless admissible. The inevitability doctrine just discussed is one such exception. The government’s claim of continuing consent could conceivably be another. The government asserts that defendant’s consent to search his vehicle carried over to the second search of his car conducted at the lot to which the vehicle was towed. We hold that because an illegal seizure occurred following the initial consent, that consent does not “continue” to justify the second search.^[8]

This is not to say that the government’s theory of continuing consent is not without additional potential failings. For instance, defendant may have revoked his consent when he closed and locked the trunk of his vehicle following the first search;^[9] defendant may not have freely and voluntarily consented to the first search; and the scope of the consent may have been exceeded. However, our previous holding makes it unnecessary to rule on these issues.

CONCLUSION

Based on the district court’s finding of fact, we hold that Officer Mahaffey’s decision to impound defendant’s vehicle was an unreasonable seizure in violation of the Fourth Amendment. Therefore, the district court’s ruling to suppress the evidence subsequently discovered was not clearly erroneous.

The mandate shall issue forthwith.