"Every time you talk to the police, you will regret it"

Here's a couple of videos that are worth an hour of your time:

If you are getting bored, skip to the second video, which says much the same thing, but there's a hot daddy bear to look at while you're listening.

Some real food for thought there. The two very serious questions I wish I could ask these guys:

1) Refusing to speak to an officer surely attracts attention to oneself. Is it really desirable to remain silent even in a completely innocuous situation? Aren't there cases where remaining silent attracts more trouble than it prevents?

2) Suppose you are a witness to a crime and you feel an ethical obligation to help solve the case. What are you supposed to do? Pay for a lawyer yourself? What is the role of social responsibility here?

I can't deny that what they say is true and correct, but it bothers me, because if everyone took their advice, we would have no law enforcement whatsoever.