After re reading the original post. I wonder if the police are just acting because someone complained and they have to be seen to do something?
The op said somebody complained about his YouTube video. Could have filmed someone or something that somebody didn't like or had the rights to. This really is a strange thing. The op also states there are videos on YouTube similar to his so he can't of done anything that drastic right?
it could have been one of those things where the OP had clearly broken some kind of law, the evidence was on you tube and the person that was complaining about it knew someone on the force which got action behind said complaint