My favorite story of the government in search of a news leak is one the late Peter Lisagor of the Chicago Daily News liked to tell about himself and Homer Bigart, then of the New York Herald Tribune--two men and two newspapers whose contributions to journalistic elan in Washington were matchless.

It was during the Eisenhower administration. Lisagor had written a piece about American prisoners of war in Korea. The day after the story appeared in the Daily News--which wasn't read daily in Washington--Bigart was in Lisagor's office in the National Press Building. Eyeing the story--as Lisagor liked to tell it--Bigart allowed that it seemed an awfully good one and asked, "Would it stand up today?"

Lisagor said he couldn't be sure, but would call his source. On the phone, Lisagor said he'd written about the subject they had discussed a few days earlier and wanted to ask whether anything had changed. Bigart, meanwhile, had picked up an extension phone. The official told Lisagor nothing had changed. Lisagor thanked the fellow and hung up. So did Bigart.

Next day a replay of the story under Bigart's byline was on the front page of the Herald Tribune, which was read daily in Washington. It was said that, when the White House received its copy, Eisenhower "went straight up." Within 24 hours, word went out to find "who talked to Homer Bigart." Well, no one did.

If there's a lesson in this anecdote, surely it is that time and energy can be squandered ransacking government offices for news leakers. Now, sadly, this administration has threatened to move in the same direction. It talks about tightening up on contacts with the press and cracking down--with "all legal means"--on officials suspected of leaking. In pursuit of the latter, the predictable odds are that it will encounter more phantoms than villains. This, despite the lie detectors that have already been employed at the Pentagon. The same kind of zeal drove the Nixon administration to the use of wiretaps.

To what purpose? To protect national security information, says the White House. Well and good, and a president is justified in going "straight up" when he is forced to confront something publicly that he may not have finished dealing with privately. But the strictures set down Jan. 12 in President Reagan's name are, for the press, too exacting and, for officials, too intimidating.

Furthermore, there are two questionable presumptions in them. One is that all leaks are unauthorized. Not so. The word that a Libyan hit squad had entered the United States for the purpose of assassinating the president and other leaks about what the administration might do about Poland had authority behind them. The occasions on which leaks come from the bosses is at least equal to those that come from the working stiffs--the "unauthorized" ones.

The other questionable presumption is that all national security information is at all times in the possession of executive branch officials. Not so, either. On any given day there is a wealth of classified material in a spread of congressional offices. It is, therefore, at least possible that one or more of the recent leaks that angered Mr. Reagan originated on Capitol Hill. It would not be unprecedented.

In all this there may be a woeful ignorance of how news is put together. The view that a troublesome story was "given" to a reporter by a discontented or dishonorable official has a correlative: that reporters have few brains of their own. Experienced officials know better. They know that reporters, who can be incorrigible among other things, keep futures books. Some know, for example, as much about the intricacies of strategic weapons issues as do the officials paid to work on them. And, if you've covered the diplomatic beat for more than one season, you can call some shots.

Listen to Dean Rusk: "A reporter is leaving the State Department at the end of the day when he sees the Soviet ambassador's car drive up. Figuring that the ambassador has brought a message, the reporter gives the machinery a chance to work, then starts calling around. After being told he's on the wrong track at several offices, he gets to the fellow on Berlin, who has been told never to lie directly to the press. The reporter says, 'John, I understand that the Soviet ambassador has just come in with a message on Berlin.' So the man says, 'Sorry, I can't say a thing about it. Can't help you on that.' Ah! He's got it. In the absence of an absolute denial, he's on the track. He figures out what the Berlin problem looks like and then calls a friend at the Soviet embassy. 'By the way, he says, what's the attitude of the Soviet Union on this particular point on Berlin.' He listens for a few moments, then he (writes) his story (for) the next morning on the message the Soviet ambassador brought in about Berlin.

"The chances are that the president will call the secretary of state and ask, 'Who in the hell has been leaking news over at the Department of State?'" (From an interview with Dean Rusk by John W. English, The Foreign Service Journal, June 1974.)

Announcing the presidential directive, National Security Council Director William P. Clark Jr. observed that reporters were doing a better job of collecting classified information than the government was of protecting it. To one who's been there, that's a familiar, not nostalgic, refrain. Still, an administration is entitled to do more than grin and bear it. But, it will achieve more if it does less regulating of the kind publicly announced.