A U.S. District Court judge has ruled that it is unconstitutional for the D.C. government to threaten or punish any of its employees for telling news reporters things their bosses don't want to hear.

In a case brought by the American Civil Liberties Union, Judge Barrington D. Parker said the city cannot issue regulations that require government employees to get permission from their supervisors before talking to the press or take disciplinary action against them for speaking critically of government policies or operations.

The city's own top lawyer, Corporation Counsel John R. Risher, had already thrown out various keep-quiet rules last August after the ACLU suit was filed.

But ACLU lawyers said yesterday that Judge Parker's order makes it certain that nothing like them can be put back into effect.

"The corporation counsel and his people should get credit for acting responsibly when they saw this complaint," said E. Edward Bruce, an ACLU volunteer attorney who handled the case. "But in the long run, it's always best to have a judicial precedent."

parker ruled that the city regulations, which have been on the books for more than a decade, violated the free speech guarantees in the First Amendment of the U.S. Constitution.

The rules were applied last December by the D.C. Corrections Department when it suspended parole officer Phillio Mattews for a day without pay after he had talked to a reporter for The Washington Post.

Matthews was quoted as saying that D.C. parole officers do not always tell employers that a job applicant has a criminal record, even though departmental policy requires them to do so.

After a departmental hearing, he was disciplined for violating a rule forbidding "release of information concerning any phase of the department's affairs" without prior approval from a supervisor.

The other outspoken employee bringing the lawsuit was Kenneth M. Cox, a fireman who told a reporter for WMAL radio about rescue equipment being taken out of service because of budget cutbacks.

Cox spoke just as he came back from a fire in October, 1975, where he had helped rescue four children and an adult, but one other child had died.

He was required to make a "special report" about what he said to a disciplinary board, but the board recommended that he not be reprimanded.

Last summer, after Risher's directive, the Corrections Department gave back to Matthews his lost day's pay and took the regulation about speaking to the press out of its employees' handbook. The fire department dropped a similar rule from its departmental order book. The city personnel office also dropped its government-wide rule which read:

"An employee shall not make public any disagreement with, or criticism of the official policies and operating practices of the District of Columbia government, nor shall he publicl y criticise or disagree with a District official who is responsible for their day-to-day application."

Employees in some D.C. government agencies, notably the Department of Human Resources and the public schools, still often say they cannot talk to reporters because they have to get clearance from their superiors.

But Assistant Coporation Counsel John Suda, who handled the case for the city, said any such requirement shouldn't exist.

"Listen, if an employee has information as a result of his job, he can tell reporters," Suda said. "There are no sneaky regulations in the background saying he can't.

"This was kind of an unusual case," Suda added, "because the corporation counsel conceded right away that the government was wrong, that it's regulations were unconstitutional . . . There may still be a lot of employees who tell you a lot of things, but that's just to avoid talking to you. It's not the regulations."