Reporting a crime is a bit different than being questioned for one, but the point still stands that by talking to a police officer you are potentially risking a lot, and should take the situation very seriously.

"Which direction did they go?!?" "Which house is on fire?!" "Does he have a gun?!" are very different questions (with different moral obligations) than "What are you doing in this neighborhood so late at night?" "Do you live around here?" "Is this your car?"

Non-urgent questions and statements should be given in the presence of an attorney, recorded, and preferably on the condition of immunity :)