(fair warning, this will autoplay the word 'Fuck' in the first 10 seconds)
You (or your friends) can go through serious inconvenience and pain, from lengthy and expensive legal battle (during which you may not be allowed to leave the state etc), to conviction and sentance, even if you don't think you've done something wrong. Innocent people and/or people who didn't realize they were breaking a law get convicted all the time.
Talking to the cops will not help your situation. Not even when they say "Look, we may have it wrong, if you just tell us what happened we can get this all cleared up." Not without a lawyer.