Do New York City police officers have a First Amendment right to protest Mayor Bill de Blasio?

In a CBS interview Sunday, Police Commissioner William Bratton said it was "very inappropriate" for officers to turn their backs on the mayor at a funeral for one of two slain officers.

While there's no indication that any officer who participated in the symbolic rebuke of Mayor Bill de Blasio will face sanction, some commentators have suggested that the protesting officers should be punished.

The speech rights of public employees can often be a legal gray area. The situation involving the back-turning cops is no exception, say legal experts.

"The answer is nobody knows," UCLA law professor Eugene Volokh told Law Blog.