Not usually illegal, but grounds for disciplinary action or firing. There are many cases of the government punishing employees for inappropriate speech while on

Not usually illegal, but grounds for disciplinary action or firing. There are many cases of the government punishing employees for inappropriate speech while on the job. Garcetti v. Ceballos (2006) is a Supreme Court decision finding that some speech of public employees is not protected. And then there's the Hatch Act (1939), which prevents most federal employees from engaging in activity that could be seen as political.