Hail to the unattributed source. Without him, or her, news would change character. It would become clearer, if less informative.

You see the trail or hear the distant voice of the unattributed source everyday. He appears this way; "a high administration official says," or "sources close to the department say," or some other version of imprecision.

Occasionally, you see his face. Two years ago, after a platitudinous briefing by a "senior State Department official," The Post ran his picture without identification. It was Secretary of State Cyrus Vance.

On May 26, The Post did it again. It ran a photo with the following caption: "Labor official who briefed reporters under a condition his name not be used." It was T. Timothy Ryan, solicitor for the Labor Department. He had conducted a briefing a day earlier under a code of behavior practiced by reporters and government officials. His briefing was called a "backgrounder." Under the rules the press could not quote him. But this time the whole system fell into low comedy.

There had been a glitch.The department's press office says it put out the word that Mr. Ryan's appearance was "on background.' United Press International, which distributes a list of Washington's daily activities, insists that the only information it received was for a "news briefing" by Mr. Ryan. So Mr. Ryan's name appeared on UPI's notices to its clients. The rules had stumbled over vocabulary.

On Monday prior to the Friday briefing, the briefing material--on regulations--had appeared in Legan Times of Washington, but without Mr. Ryan's name. On Wednesday most of the same material had been published in The Wall Street Journal. Mr. Ryan's name appeared in the article.

When reporters arrived for the briefing, they were directed by signs to the meeting room. Some of the signs included Mr. Ryan's name. On arrival, however, reporters were told that this was indeed a "backgrounder," and Mr. Ryan was not to be quoted.

Since the rules, this time, had been botched, The Post used one way around the code, The New York Times another. Both were insider attempts to ridicule the process. The Post used the mysterious picture. The Times did it in print this way: "The spokesman specified that his name not be used in new accounts of the briefing. Earlier, however, United Press International carried an announcement of a scheduled news briefing by T. Timothy Ryan. . . . "

Thus, two of the nation's leading newspapers obeyed the letter, and violated the spirit, of tribal conventions.

There are four rough categories of attribution, rough because there are variations. "On the record" means the reporter can quote his source by name. No games. "Backgrounder, means the reporter can use the material but not the source. "Deep backgrounder" gets murky. It calls on the reader for an act of faith, and it produces some familiar phrases: "it is known that" or "it is believed that." In other, words, the fact that it came from a source cannot be revealed. Finally; there is "off the record." It means the reporter can't use it at all.

The problem with all this is that, unless one is a journalistic junkie, the code and its vocabulary call credibility into question.

The reader and the listener want to know who is saying what and why as clearly as possible.

The code between reporter and source is a necessary evil because there is information in this city that should be made public--information that is inaccessible without the protection of a source. But then are excessess when a reporter doesn't press his source enough or when the politician or civil servant attempts to obscure information that doesn't deserve protection.