In what circumstances will the exclusionary rule of search and seizure be used to justify a search without a warrant?

It is settled by a series of decisions of this court that in the absence of such evidence we will not entertain the People's claim of justification: "The purpose of the exclusionary rule to deter unreasonable searches and seizures by law enforcement officers would clearly be frustrated if the courts were required to uphold a search conducted on unreasonable grounds simply because the prosecuting authorities belatedly managed to devise an alternative theory on which the arresting Officer could have acted reasonably if he had known of it. Compliance with the fundamental guarantees of the Fourth Amendment is not a game to be won by inventive counsel, but a practical, day-to-day responsibility of law enforcement personnel. Accordingly, just as a warrantless arrest or search [24 Cal.3d 311] cannot be justified by facts of which the officer was wholly unaware at the time (citations), so also it cannot be justified on theories thereafter invented for the consumption of reviewing courts (citations)." (Italics in original; fn. omitted.) (People v. Superior Court (Simon) (1972) 7 Cal.3d 186, 198, 101

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