The United States Supreme Court in United States v. Ross vastly simplified the process of searching closed containers found in an automobile during a lawful Carroll search yet, at the same time, placed in question the importance of the search warrant in the scheme of fourth amendment jurisprudence by equating the policeman's determination of probable cause with that of the magistrate.
Donald L. Dalton
United States v. Ross: Search and Seizure Made Simple,
10 Pepp. L. Rev.
Available at: http://digitalcommons.pepperdine.edu/plr/vol10/iss2/3