The logical conclusion of your reasoning is that the police should gather all evidence that's physically possible. Just go and ransack people's homes, looking f

The logical conclusion of your reasoning is that the police should gather all evidence that's physically possible. Just go and ransack people's homes, looking for evidence, no warrant involved. Once they've got all the evidence they can collate it all and decide which people were probably really nasty, try to build a case - or in really extreme cases, just claim that the already-gathered evidence shows something so heinous that they needn't bother with that. But that initial ransacking of our personal space without warrant (i.e., without probable cause) is the problem, not just the use of that evidence in a trial. People should be secure in their homes without needing to worry about law enforcement deciding it's time for periodic fishing expedition.