Are Undercover Police Guilty of Lying?

There are two ways to view this.

One is that undercover police are no different than an actor in a play or TV show or movie. They are playing a role that society has authorized them to play.

The second is that in moral theology it is said that the truth is required insofar as the other person has a right to the truth. A criminal who breaks the law cannot possibly claim a right to know if the other person is actually a fellow criminal or the police.