WASHINGTON - Here we go again with the culture of the polygraph.

In 1985, President Reagan, who complained of being "up to my keister in leaks," ordered lie detector tests for a host of officials, including cabinet members. He backed off when Secretary of State George Shultz threatened to resign, saying that management by intimidation was no way to protect national security.

Now, CIA Director Porter Goss is returning to the era of the polygraph after a couple of leaks that caused the administration intense embarrassment.

Last December, The New York Times broke the Pulitzer Prize-winning story of President Bush's secret authorization to the National Security Agency to conduct domestic eavesdropping without warrants.

Last November, the Washington Post broke the Pulitzer award-winning story of the CIA interrogating some of its most important prisoners in secret prisons in Eastern Europe.

Mary McCarthy, who worked in the office of the CIA Inspector General, which has agency-wide access to classified material, was summarily fired. CIA sources said that after a polygraph, she admitted to having been the source of the leak about CIA prisons.

The controversy took on a bewildering aspect when Ms. McCarthy denied being a source of the prison story - denied even knowing about the prisons. The agency insisted that one of its officers was fired for having "knowingly and willfully shared classified information." It did not name McCarthy, although she was the one who was discharged.

Colleagues of McCarthy said they couldn't imagine her leaking classified information. I have never met her, but I can.

During my reporting days it was my experience that an official willing to bend the secrecy rules was usually someone using this last resort means to protest against the effort to hide an activity that the public needed to know about.

For example, in 1975, the CIA Inspector General wrote a report that the agency had been working on plans for the assassination of Fidel Castro, acting in concert with the Mafia, if you can believe it.

My report on CIA assassination plots on CBS led to investigations by a commission named by President Ford and headed by Vice President Nelson Rockefeller, and a congressional investigation headed by Sen. Frank Church. I am unwilling, even at this late date, to identify my source. But I will say I am convinced that my source was confident of acting in the public interest.

I think the same was true of Mary McCarthy or whoever it was that leaked the prison story - true whistle-blowers serving the public interest.

Daniel Schorr is the senior news analyst at National Public Radio.

© 2006 The Christian Science Monitor

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