Can I film a soccer game in the local park?
The legal answer to your question is sometimes. If no one asks you not to you can certainly can. If the league or party that rented the field from the city asks you not to or makes an announcement you may not (depends also on the rental contarct with municipality). If you continue to tape after they ask you not to or argue with a cop about it you can get a ride to jail like Kramer. That's the simple part. The tricky part of copyright come later in that even if you legaly film a pickup game in a public park you cannot necessarily use the images of discernible people without violating their "rights to publicity" (Rights to publicity laws vary from state to state. They are particularly harsh in places like California where the Hollywood types have gotten the legislature decades ago to pass strong publicity laws protecting their likeness. So if you see Bono on the sidewalk in NY you can take his picture, but if you put that picture on a t-shirt or poster and you can get sued and if you do you will lose. It is even goofier when the media is involved. They can take his picture and put it on the front page of their tabloid (clearly to draw buyers and make money) but that is protected speech. Copyright, trademark, and publicity can be endlessly complex. This case in Utah is not - Private event (public venue does not make what happens there public domain) so when asked not to film everything afterwards is a no-no.