IT COMPELS attention when a Cabinet officer, having lost an important argument on the inside, goes public in dissent on the outside. Secretary of State George Shultz has done this now on the use of lie detectors. Hard on the heels of a presidential directive extending polygraph examinations well beyond the intelligence agencies where their regular use is an established condition of employment, Mr. Shultz has said that he considers them unreliable and erratic. He adds: "The minute in this government I am told that I'm not trusted is the day that I leave."

Mr. Shultz was resoundingly right. In response, the president quickly excused him (and himself) from taking a test. But the implications of the secretary's statement surely went beyond the immediate question of whether he himself would be asked to submit to such a test. Having suggested that he would consider such a request an assault on his own integrity and trustworthiness, he has surely also suggested that administering the tests within his department would amount to a similar assault on the integrity and trustworthiness of his employees.

Lie detector tests are not simply intrusive. As Mr. Shultz indicated, they are also fallible. They do rest on a presumption of distrust. A wise president, rather than offering a special dispensation to one person, would make plain that he does not want in his Cabinet anyone who would take the test.

From the start this administration has tended to tilt hard to the security side of security-privacy issues. The year's spy disclosures enabled it to push forward its lie detector program. But the new directive has the look of a hasty catchup meant to cover recent embarrassments and to avoid the burden of less intrusive security techniques or the shame of admitting how often the people charged with protecting the government's secrets have been incompetent. It is the easiest (and commonest) thing in the world for these people, when one of their failures becomes prominent, to whine that they don't have enough special draconian laws and gimmicks to do the job. It is a form of covering up a faulty record by blaming it on something else.

The argument is made that the government has an evident, large and growing need to protect its secrets and an unquestionable right to do so and that lie detectors are useful and can be used discreetly and respectably. But against these claims must be set the dispiriting record of abuse of this instrument and the special alarms of intrusiveness it sets off. It is good to have Secretary of State Shultz taking a stand on principle here. He is right. The government should listen to him and absorb the full implication of what he is saying.