IIRC, Congress took up the issue of restricting speech of federal employees.
...
SCOTUS -
http://www.latimes.com/news/nationworld/nation/la-na-scotus31may31,0,1570961.storyCourt Curbs the Speech of Public Employees
Justices rule that the 1st Amendment doesn't shield public-sector whistle-blowers.
By David G. Savage, Times Staff Writer
May 31, 2006
WASHINGTON — The Supreme Court on Tuesday restricted the free-speech rights of the nation's 21 million public employees, ruling that the 1st Amendment does not protect them from being punished for complaining to their managers about possible wrongdoing.
Although government employees have the same rights as other citizens to speak out on controversies of the day, they do not have the right to speak freely inside their offices on matters related to "their official duties," the high court said in a 5-4 decision.
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So...it's not the same as in being a whistle-blower in this situation. But note this paragraph in the piece: "However, lawyers for city and state agencies said the decision will prevent routine internal workplace disputes from becoming federal court cases."