The Supreme Court's decision to limit free-speech protections for whistleblowers working for the government, distressing as it was, can serve as a call to action. Congress must provide a safety net for public workers that, according to five justices, does not exist in the U.S. Constitution.

In the 5-4 decision, the court ruled that government employees must accept limitations on their right to speak out on matters related to their "official duties." In this case, they faulted the action of a Los Angeles district attorney who had urged supervisors to dismiss a pending criminal case because of police misconduct.

The prosecutor, Richard Ceballos, blew the whistle because he said a sheriff's deputy may have lied to obtain a search warrant. His advice was rejected; then he was transferred to a post farther from home and denied a promotion.

"When a citizen enters government service, the citizen by necessity must accept certain limitations on his or her freedom," said Justice Anthony M. Kennedy in the majority opinion.

The high court thus tossed out Ceballos' legal claim that he had been punished for speaking out. That then sends a message to public workers that they have no shield once they question authority, even if they send their complaint up through the chain of command.

Those defending the ruling say it merely gives government managers authority to make decisions without fearing a disgruntled employee might make a federal case out of it. But the effect will be chilling on public workers who otherwise might act to correct a wrongdoing.

These are employees on the public payroll, and they above all deserve the right to report to a superior when the public's work has gone awry. The health of our democracy relies on people believing they have some influence over how government functions.

It was a bad decision by the court, one that sets an unfortunate precedent. The justices found that government workers aren't protected while on duty, imposing a disturbing distinction that doesn't exist in the First Amendment text.

Congress should move quickly to enshrine public workers' rights to dissent in federal law. And government officials must not use this lapse as an excuse for an abuse of power in the meantime.