When? It isn't illegal or anything yes they can. Added: Absolutely - and they can demand that you produce identification if they have reason to believe that you may be impersonating one.
If you are a police officer you would not need to ask. A police officer doing his duty will treat another police officer as any member of the public (if they are out of uniform and off duty).
A Police Officer can ask you anything from pertaining to the reason they stopped you or began questioning you, to the weather and the latest scores for games. The only time a Police Officer cannot...
The police can ask a minor any question they can ask of anyone else. Depending on the circumstances and the state where the questioning is taking place, the police may be required to have a parent or...