"There are court cases that give the confidence necessary. " NO!

many times police will made up "plausible way" how they uncovered something, but this "plausible way" was constructed after the "secret" or illegal way was employed to do it.

rephrase : police will do illegal thing to obtain info where you stash your drugs. for example installing NGO Pegasus to your phone, gps tracker under car... so they already have that info. then they call anonymously 911 saying there is smell of gas on street. (maybe they even spray some of mercaptan to make it even more plausible) firefighters, etc will come investigate gas leak and police will say that they uncovered drug stash in investigation of gas leak... illegal way to obtain info, then brainstorming how to make that data available "lawfully". they will not tell in front of judge/court about first part... so no your assumption is not correct.

in computer world it is million time easier.

99% of youtube videos about criminals failing at operational security is intentionally bad information.

IF you are believed to be criminal / "bad person" police(men) will justify doing almost anything, because you are bad person IN THEIR EYES.

also they are trained to and expected to disinform :

For example, Ross Ulbricht. every news paper said that "closing his laptop lid will lock his computer and police will be unable to decrypt it" they pushed it and said it so many times that researchers jumped on LUKS and in 1.5 years there was almost complete rewrite of LUKS.... (not even talking about constant TOR effort)

Whole not closing his notebook also proves that they obtain data legally. It does not say they did not have that data already.

One info can mean multiple things to multitude of people.