CBS NEWS, responding to criticism of a documentary on Vietnam, has done something very hard for most organizations to do: it has examined the criticism without flinching and admitted fault. The review, undertaken, as CBS news chief Van Gordon Sauter explained, to protect CBS News' most important asset--its credibility--does exactly that.

"The Uncounted Enemy: A Vietnam Deception," which ran last Jan. 23, said Gen. William Westmoreland had led a "conspiracy" to pass to the White House deflated estimates of enemy strength in order to sustain public support for the war. Confirming one common--though contested--Vietnam- era view of official venality, the documentary made a splash. In May, however, TV Guide magazine published an investigative report asserting that CBS had not so much discovered a conspiracy as set out to prove one and had tailored its investigation to fit. For instance, "CBS paid $25,000 to a consultant on the program without adequately investigating his 14-year quest to prove the program's conspiracy theory," it "violated its own official guidelines by rehearsing its paid consultant before he was interviewed on camera," and so on. In response, CBS conducted its own review; a summary was released the other day.

While formally "standing by" the documentary, CBS backed off the charge of "conspiracy." It said it had not sought out enough persons "who disagreed with the broadcast premise" of official deception. And it acknowledged inadequate compliance with its news standards, to wit: one Westmoreland critic was interviewed twice "to elicit a stronger interview"; another was allowed to view interviews of others before going on camera himself; the show's consultant was not identified as paid; by "oversight," material was twice transposed from one set of events to another; four times, answers from several questions were combined into one answer. Further, a letter from Gen. Westmoreland, in which he followed up his interview, was not heeded, an available Westmoreland supporter was not tracked down and no material was used from a three-hour interview with presidential aide Walt W. Rostow.

CBS News was very gutsy to tackle such a vital and tender topic in a documentary in the first place. It is now taking another look at the issue. It is appointing a vice president to hear complaints, internal and external, and it will require the principal correspondent on these shows to be fully involved-- not simply to come in late for a few interviews. Already there is some criticism of Mr. Sauter for answering at all to outside criticism: dark clouds of corporate or commercial pressure are said to be hovering. We think it's something else. We think it's journalism that is self-confident enough to be self- critical. That is the only credible kind.