Is a search of defendant's car valid as an inventory or impound search?

[3][4] The prosecution argues that the search of defendant's car was also valid as an inventory or impound search. Such searches are an exception to the search warrant requirement, but only if they are conducted pursuant to "standardized criteria" or an "established routine," that is, if the police agency has a policy regarding conducting such searches and if the policy is followed in the particular case. ( Colorado v. Bertine (1987) 479 U.S. 367, 374-375, fn. 6, 107 S.Ct. 738, 93 L.Ed.2d 739; Florida v. Wells (1990) 495 U.S. 1, 4, 110 S.Ct. 1632, 109 L.Ed.2d 1; People v. Williams (1999) 20 Cal.4th 119, 126, 83 Cal.Rptr.2d 275, 973 P.2d 52.) Defendant argues that the search of his car in the present case does not fall within this exception as there is no evidence in the record that the police had such a policy, or that they followed it in the present case. Defendant is correct.