Supreme Court Justice Louis Brandeis once wrote that sunlight is the best disinfectant. Government officials, however, often prefer to work under a cloak of darkness, letting them use their power in ways that can’t be seen. That makes their lives easier while undermining democracy, which depends on an informed citizenry.

One of the valuable things journalists do is to pierce that darkness to let people know what is being done in their name – and decide whether they approve. But in recent years, the government has fought back by trying to force journalists to appear in court to disclose their confidential sources.

The point is not merely to find out who has leaked secrets. It’s to frighten potential leakers and thus shut down the flow of information.

No fewer than 36 states have enacted shield laws to protect reporters who are merely doing their jobs, but there is no protection at the federal level. During last year’s presidential campaign, Barack Obama indicated he understood the problem. He endorsed a tough federal shield law that would protect journalists from being forced to identify their sources.

But now that he’s in charge of the executive branch, he is less convinced that government leaks serve the public interest. So the administration is trying to weaken the shield proposals now before Congress.

A bill passed by the House establishes strong safeguards against overzealous prosecutors. It would exempt journalists from being forced to testify except in a few narrow circumstances – such as when their testimony could prevent death, injury, terrorist acts or clear harm to national security. Even then, the government would have to show that the information it demands is essential, that it can’t be obtained in any other way and that the disclosure would serve the public interest.

But the Obama administration would tilt the balance in favor of the government – which would be able to force a journalist to talk merely by showing that the revelation was “reasonably likely” to damage national security.

The courts would have to give great weight to the claims of the government, despite its obvious vested interest in keeping its activities from scrutiny.

The news media, meanwhile, would not be able to protect itself by showing that the public interest was greater than the alleged harm. The burden, in effect, would be on the journalists to show why they should not be turned into unpaid investigators for law enforcement.

After taking office, President Obama issued a memo to heads of federal departments and agencies declaring, “My administration is committed to creating an unprecedented level of openness in government.”

If he means that, he needs to support a federal shield law that would foster openness instead of retarding it.

The above editorial was originally published Oct. 7 by the Chicago Tribune. Content was made available by MCT Campus.