“There’s not that fine a line between cooperating with law enforcement and unreasonable search and seizure. Being asked to identify yourself is not out of line, and is compelled legally in most states.”
The requirement to provide your identity is only required if a crime has been committed, correct? So the correct response would be to ask what crime I was suspected of? Peeking into cars is not a crime although it may be somewhat suspicious.
Most states require you to identify yourself when requested to do so by an officer of the law. Hence my original reply ... answer the officer's questions, or stand on principle and be taken in for questioning. As far as any "crime," I'd say suspicion of breaking and entering, given the nature of the call that had the officer out there in the first place.