In Florida v. Wells (1990) 495 U.S. 1 the Supreme Court held the trial court should have suppressed marijuana found when officers opened a locked suitcase while inventorying a vehicle. (Id. at p. 2.) Reiterating the limitation on inventory searches it had announced in Colorado v. Bertine (1987) 479 U.S. 367, the Court explained "standardized criteria or established routine must regulate the opening of containers found during inventory searches" to safeguard the "principle that an inventory search must not be a ruse for a general rummaging in order to discover incriminating evidence." (Wells, at p. 4.) "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.'" (Ibid.) Because the record in Wells contained no evidence of any policy of the law enforcement agency whose officers had conducted the search regarding the opening of closed containers during inventory searches, the Supreme Court concluded the marijuana found in the suitcase should have been suppressed: "Absent such a policy, the . . . search was not sufficiently regulated to satisfy the Fourth Amendment . . . ." (Id. at p. 5.) In People v. Williams (1999) 20 Cal.4th 119, the California Supreme Court reinforced the Bertine and Wells standard, emphasizing the "prosecution must always prove the existence of a policy supporting an inventory search . . . ." (Williams, at p. 138.) "Because of the risk that an inventory search will be 'a ruse for a general rummaging,' a risk that this case particularly exemplifies, a valid inventory search must adhere to a preexisting policy or practice. This rule may require the prosecution to prove more than the existence of some general policy authorizing inventory searches; when relevant, the prosecution must also prove a policy or practice governing the opening of closed containers encountered during an inventory search." (Ibid.; see Florida v. Wells, supra, 495 U.S. at pp. 4-5.) The officers in Williams found methamphetamine in closed leather bags inside the defendant's truck during the inventory search. Because the prosecution did not prove the leather bags had been opened "pursuant to a policy or practice," the Court held the warrantless search was unlawful. (Williams, at p. 138.)