Is there any case law or case law in which a plaintiff has been found to be in breach of his right to speak freely in a public office?

On the other hand it is obvious that the mere assertion that one is exercising or has exercised his right of free speech does not automatically clothe the speaker with full and perpetual immunity from an obligation to explain what he has said. Indeed we can conceive of many situations where an inquiry into the exercise of the right to speak is justified, as it is in the instant case, by need for an appropriate public or professional body to ascertain the true meaning of the language used by the speaker. (Cf. Konigsberg v. State Bar, Supra, 366 U.S. 36, 44--47, 51, 81 S.Ct. 997, 6 L.Ed.2d 105.) It is the proper accommodation of these competing considerations which must concern us here.