Chief Justice Rehnquist
delivered the opinion of the Court.
A Florida Highway Patrol trooper stopped respondent Wells for speeding. After smelling alcohol on Wells’ breath, the trooper arrested Wells for driving under the influence. Wells then agreed to accompany the trooper to the station to take a breathalyzer test. The trooper informed Wells that the car would be impounded and obtained Wells’ permission to open the trunk. At the impoundment facility, an inventory search of the car turned up two marijuana cigarette butts in an ashtray and a locked suitcase in the trunk. Under the trooper’s direction, employees of the facility forced open the suitcase and discovered a garbage bag containing a considerable amount of marijuana.
Wells was charged with possession of a controlled substance. His motion to suppress the marijuana on the ground that it was seized in violation of the Fourth Amendment to the United States Constitution was denied by the trial court. He thereupon pleaded nolo contendere to the charge but reserved his right to appeal the denial of the motion to suppress. On appeal, the Florida District Court of Appeal for the Fifth District held, inter alia, that the trial court erred in denying suppression of the marijuana found in the suitcase. Over a dissent, the Supreme Court of Florida affirmed. 539 So. 2d 464, 469 (1989). We granted certiorari, 491 U. S. 903 (1989), and now affirm (although we disagree with part of the reasoning of the Supreme Court of Florida).
The Supreme Court of Florida relied on the opinions in Colorado v. Bertine, 479 U. S. 367 (1987); id., at 376 (Blackmun, J., concurring). Referring to language in the Bertine concurrence and a footnote in the majority opinion, the court held that
“[i]n the absence of a policy specifically requiring the opening of closed containers found during a legitimate inventory search, Bertine prohibits us from countenancing the procedure followed in this instance.” 539 So. 2d, at 469.
According to the court, the record contained no evidence of any Highway Patrol policy on the opening of closed containers found during inventory searches. Ibid. The court added, however:
“The police under Bertine must mandate either that all containers will be opened during an inventory search, or that no containers will be opened. There can be no room for discretion.” Ibid.
While this latter statement of the Supreme Court of Florida derived support from a sentence in the Bertine concurrence taken in isolation, we think it is at odds with the thrust of both the concurrence and the opinion of the Court in that case. We said in Bertine:
“Nothing in [South Dakota v.] Opperman[, 428 U. S. 364 (1976),] or [Illinois v.] Lafayette[, 462 U. S. 640 (1983),] prohibits the exercise of police discretion so long as that discretion is exercised according to standard criteria and on the basis of something other than suspicion of evidence of criminal activity.” 479 U. S., at 375.
Our view that standardized criteria, ibid., or established routine, Illinois v. Lafayette, 462 U. S. 640, 648 (1983), must regulate the opening of containers found during inventory searches is based on the principle that an inventory search must not be a ruse for a general rummaging in order to discover incriminating evidence. The policy or practice governing inventory searches should be designed to produce an inventory. The individual police officer must not be allowed so much latitude that inventory searches are turned into “a purposeful and general means of discovering evidence of crime,” Bertine, 479 U. S., at 376 (Blackmun, J., concurring).
But in forbidding uncanalized discretion to police officers conducting inventory searches, there is no reason to insist that they be conducted in a totally mechanical “all or nothing” fashion, “[inventory procedures serve to protect an owner’s property while it is in the custody of the police, to insure against claims of lost, stolen, or vandalized property, and to guard the police from danger.” Id., at 372; see also South Dakota v. Opperman, 428 U. S. 364, 369 (1976). A police officer may be allowed sufficient latitude to determine whether a particular container should or should not be opened in light of the nature of the search and characteristics of the container itself. Thus, while policies of opening all containers or of opening no containers are unquestionably permissible, it would be equally permissible, for example, to allow the opening of closed containers whose contents officers determine they are unable to ascertain from examining the containers’ exteriors. The allowance of the exercise of judgment based on concerns related to the purposes of an inventory search does not violate the Fourth Amendment.
In the present case, the Supreme Court of Florida found that the Florida Highway Patrol had no policy whatever with respect to the opening of closed containers encountered during an inventory search. We hold that absent such a policy, the instant search was not sufficiently regulated to satisfy the Fourth Amendment and that the marijuana which was found in the suitcase, therefore, was properly suppressed by the Supreme Court of Florida. Its judgment is therefore
Affirmed.