One sure way to make a reporter furious is to publish a letter to the editor that labels his or her story "inaccurate and misleading." Morton Mintz, Post reporter for more than a quarter century, author of six books and winner of six national journalism awards, who digs intensively and knows how to disclose others' faults, got the treatment himself 10 days ago.

The letter writer was Elmer B. Staats, well-regarded public official whose career includes heading the General Accounting Office, being deputy director of the then Bureau of the Budget, presiding over the American Society of Public Administration, serving on numerous boards and receiving a Presidential Citizens Medal and the Rockefeller Public Service Award.

The Staats-Mintz in-print confrontation illustrates how The Post deals with such differences -- a process that is imperfect, often leaving both parties dissatisfied, but constituting a step tow dealing with the great power of a near- monopoly publication.

The fracas began three weeks ago with the article, "GAO Auditing Defense Firms -- For Nearly 20 Years, the Agency Kept Hands Off." The story reported on an exchange of letters between Sen. William Proxmire (D-Wis.), a longtime watchdog on defense spending, and Comptroller General Charles A. Bowsher, who has headed GAO since 1981. Mr. Mintz reported that GAO has sent 50 auditors into 10 major arms suppliers after nearly 20 years of keeping "hands off of the books of defense contractors."

While Mr. Staats was not mentioned by name until the 14th paragraph of the lengthy piece, it was clear to Washington cognoscente that the 20 years included Mr. Staats' term as comptroller general. Two paragraphs later there was no mistaking the accusation: "He ended his 15-year term without having once authorized a GAO-initiated contractor audit." (Mr. Staats was not asked for comment. If he had been, Mr. Mintz might not have been the unhappy target of a letter to the editor.)

An indignant Mr. Staats fired off a letter criticizing not only the message in the story, but also Mr. Mintz, the messenger. Sen. Proxmire and Mr. Bowsher went unmentioned. Yesterday the senator defended Mr. Mintz's story as "accurate and timely" in a letter to the editor.

At the heart of the issue was a difference over how to deal most effectively with unscrupulous defense contractors. In pre-Staats days there were GAO probes, followed by headlined charges quoting the comptroller general. A GAO history acknowledges that in the mid- '60s the number of reports on defense contracts declined, the content became more general, the titles less explosive and names were usually omitted. Mr. Staats argues this approach was "more effective and saved more money."

When Mr. Staats' retort arrived in the editorial department, Kathryn Stearns, an editor, following customary practice, sent the letter to Mr. Mintz for any comment. Often reporters point out misstatements, which can lead to further questions of the letter writer, and, if there are many errors, the rejection of the letter. Mr. Mintz, who felt comments were futile, responded only with: "It's full of baloney. I've got lots of documentation to prove it."

Meg Greenfield, editorial page editor, said disagreements between reporter and aggrieved posed difficult problems. "It's not a true or false test. There's the weight of material; there are the interpretations. While supporting reporters, we have to come down on the side of someone who has been the object of criticism and give him a chance to reply. Of course, we take out the stuff that is personal and vicious." Mr. Staats' prominence obviously weighed in the decision to publish his letter.

Why not permit a reporter to append a paragraph taking exception?

Miss Greenfield's response was, "A reader should get a say, and if there were a footnote the reader wouldn't get the last word even on that day. The reporter didn't let Staats write footnotes on his piece." Miss Stearns added, "It would perpetuate an arrogance of the press that readers don't like."

There are some inconsistencies: Occasionally a letter to the editor is accompanied by an editorial defending the paper or a reporter. Sometimes a wounded author's letter in Book World is followed by a critic's response.

But, getting back to the case at hand, suppose there had been no letter from Sen. Proxmire defending the reporter?