President George Bush, Attorney General John Ashcroft and Vice President Dick Cheney, who dislike leaks about their war plans, made two mistakes when they tried to persuade members of the House and Senate intelligence committees to submit to lie-detector tests. They relied too heavily on lie detectors, now called polygraphs. And they rushed too fast into the hazardous area of leak detection.

Lie detectors are notoriously unreliable. The U.S. Supreme Court said in a 1998 decision that “there is simply no consensus that polygraph evidence is reliable. To this day, the scientific community remains extremely polarized about the reliability of polygraph techniques.” The court quoted one field study suggesting that the accuracy rate was “little better than could be obtained by the toss of a coin,” that is 50 percent. In the Reagan administration, Secretary of State George P. Shultz found it so degrading to be ordered to take a lie-detector test that he publicly threatened to resign.

The lie detector business started in the early 1900s, according to the on-line magazine Salon, as a promotion by one William Marston, “a publicity hungry psychologist.” The Berkeley, Calif., police department took it up, and polygraph schools sprang up across the country. At first, the machines measured only blood pressure and respiration. Galvanic skin resistance – sweatiness – was added later. Federal, state and local government agencies now use lie detectors routinely in investigations and employment procedures. But Congress in 1998 outlawed pre-employment polygraph screening in private industry except for jobs like security guards and armored-car drivers. And a private company employee can’t be fired for refusing to take a polygraph test.

As for leak detection, much as it hates to see its secrets exposed, the Bush administration heads into risky ground when it tries to stop the leaks. Even the hawkish editorial page of The Wall Street Journal takes a tolerant view of leaks. In an editorial assailing the left wing of the Democratic Party and The New York Times for agitating against a war with Iraq, the Journal said: “In our porous democracy, it is impossible to keep such internal debates [over how to topple Saddam Hussein] entirely private. The leaks also help inform the media and the public, and as long as they don’t endanger an imminent battle plan, we don’t oppose their publication. Already the Times has printed so many ‘secret’ war plans that Saddam can only be thoroughly confused.”

So President Bush, Mr. Ashcroft and Mr. Cheney would do well to cool their anger over leaks, accept them as something that comes with running the country, and take it easy with lie detectors.