STEVE INSKEEP, host:
Also today, a federal grand jury is expected to hear testimony in the investigation of a national security leak. Prosecutors are examining Julian Assange, the founder of WikiLeaks.
NPR's Carrie Johnson has the story.
CARRIE JOHNSON: National security experts say they can't remember a time when the Justice Department has had so many criminal cases based on leaks of government secrets.
Steve Aftergood has been following five separate prosecutions, part of what he calls a tremendous surge by the Obama administration.
Mr. STEVE AFTERGOOD (Project on Government Secrecy): For people who are concerned about freedom of the press, access to national security information, it's a worrisome development.
JOHNSON: Aftergood says some of the most important disclosures of the past decade, including abuses by the U.S. military at the Abu Ghraib prison in Iraq, came out because people concerned about overreach blew the whistle on the government.
Mr. AFTERGOOD: Leaks serve a very valuable function as a kind of safety valve. They help us to get out the information that otherwise would be stuck.
JOHNSON: The Obama Justice Department doesn't agree.
Aside from the ongoing WikiLeaks investigation, federal prosecutors have brought criminal charges against four other people: a former State Department employee; an operative who used to work at the CIA; a one-time National Security Agency analyst going to trial next month in Baltimore; and a former FBI translator who pleaded guilty and was sentenced to almost two years in prison.
Again, Steve Aftergood.
Mr. AFTERGOOD: As aggressive as the Obama administration has been in pursuing and prosecuting leakers, the signal that the administration is getting from Congress is, why aren't you doing more?
JOHNSON: Exhibit A: a pair of oversight hearings last week, where Republicans blasted the Justice Department for deciding not to prosecute Thomas Tamm. Tamm's a former government lawyer who admitted to telling the New York Times about a secret electronic surveillance program.
Iowa Republican Senator Charles Grassley said the case raises questions about whether prosecutors had gone soft on leaks.
Senator CHARLES GRASSLEY (Republican, Iowa): I am concerned that the decision not to prosecute anyone related to this specific leak may indicate a reluctance to enforce the law. Leaks of classified information threaten the lives of our agents and allies in the field.
JOHNSON: The House and Senate Intelligence Committees have gone even further. They want the intelligence community to create new computer systems to detect leaks and to give government officials the power to yank away the pensions of suspected leakers.
Mr. ABBE LOWELL (Attorney): Going after leakers of classified information, if you will, is low-hanging fruit to show that you're tough in national security issues.
JOHNSON: That's Abbe Lowell. He's an attorney in Washington. He's defended two people accused of leaking sensitive information.
Mr. LOWELL: Other than the media, who are willing recipients of this material, there's not a constituency out there that basically is outraged when you go after a leaker.
JOHNSON: Lowell says that being a government employee doesn't mean you forfeit your First Amendment rights to share information or talk to people as part of your job. And he says many federal employees shake their heads at double standards. Bosses can leak information to favorite reporters with no punishment, but federal workers face a crackdown if they do it.
Mr. LOWELL: It is so arbitrary and capricious for the prosecutors to decide that some leaks are criminal and other leaks are what we actually want to have happen.
JOHNSON: Advocates for open information say the government should use less severe tools, such as financial penalties or removing a worker's security clearance, before pulling out all the stops and bringing an indictment.
Carrie Johnson, NPR News, Washington.