IN MAY the Supreme Court heard an argument in a libel case that raised the question of whether all published expressions of opinion -- in this case the statements in an Ohio sportswriter's column -- might be judged libelous and how, in close cases, one distinguishes between fact and opinion. Newspapers then, including this one, expressed alarm at what seemed to be a step back from what appeared to be the clear teaching of the federal courts. Although the statements in the Ohio case did present a muddy mixture -- asserting, for instance, that "anyone who was there knew in his heart" that a high school coach had perjured himself -- and although the court did not rule the statements libel but only sent them back to the lower court for further examination, the danger of the decision was the possibility that a flood of litigation would promptly emerge to test the new borders of libel. That fear now takes a faintly absurd but still troublesome twist with the lawsuit of writer Dan Moldea against The New York Times, which Mr. Moldea accuses of having libeled him by publishing a negative review of his book "Interference: How Organized Crime Influences Professional Football."

Reviews are understandably a tempting target for libel suits, whether of books, plays, restaurants or anything else: a fiercely negative review can close a play, slash a restaurant's business or cut sharply into a book's sales. Mr. Moldea's suit demands $10 million in damages, saying the review "falsely portrayed him as a sloppy and incompetent journalist" and that it sharply reduced his fees as a lecturer. But reviews have also till now proved more or less impermeable to libel suits, as cases cited in the Media Law Reporter show. A 1985 complaint against a book's review of a Chinese restaurant ruled as non-libelous a statement that "it is impossible to have the basic condiments on the table"; a 1978 New York case ruled non-libelous a description of an entertainer as a "non-professional embarrassment" and "tone-deaf mediocrity." Even were a negative statement to be found libelous, some lawyers suggest, awarding any damages could depend on showing that a loss of sales came from the false statements of fact and not from the reviewer's overall negative opinions. Precisely because they are intended as guides for would-be consumers, the protection of a reviewer's ability to express such opinions carries a strong public interest; wherever the boundary between fact and opinion may lie, the reactions of reviewers would seem to fall on its safer side.

Mr. Moldea's complaint, at first glance, looks milder than this, and his claim of factual falsity seems something of a stretch. The review does, as he charges, accuse him of "sloppy journalism"; it goes on to give a string of examples, including spelling errors. True, no one can be sure how the rule will stand under future Supreme Courts. But for Mr. Moldea to show that this sort of thing is provably false fact, rather than opinion, would require a large and unwarrantable step past anything established in the Supreme Court's handling of the Ohio case.