Illegal to film police?
That would have to be a state law, and maybe that's how it is in some states, but I'm pretty sure it's not like that in most states. There was just a thing recently in... Buffalo? I think, about it being legal to film police.
And yeah, if a civilian breaks the law and evidence comes from that, it's not inadmissible, unless they were acting as an agent of the police.
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Connecticut Huskies