THE SUPREME COURT'S latest libel decision accurately reflects the unsettled and confused character of the law as it now stands. Justice Powell, delivering the court's judgment, was joined by only two other judges. Chief Justice Burger wrote a concurring opinion supporting Mr. Powell's conclusion but attacking the precedent, also written by Mr. Powell, that it modified. Justice White, separately, did the same. The only opinion to be supported by as many as four judges was Justice Brennan's dissent. The chief effect of this case will be to deepen the complexity of the law of libel and the uncertainty that surrounds it.

The case began with a clear and acknowledged error of fact. A credit rating agency, Dun and Bradstreet, gave five clients an incorrect report that a certain Vermont builder had filed for bankruptcy. Dun and Bradstreet issued a correction a week later, but the builder found the response unsatisfactory, sued and won. The question to the Supreme Court was whether the company could properly collect the $300,000 in punitive damages that the jury awarded in addition to $50,000 in compensation.

In the past the court has allowed punitive damages only in cases where plaintiffs showed actual malice -- which, as the court uses the term, means that the people publishing the libelous statement either knew it to be wrong or had serious doubts about its truth. But now the court says that all those previous decisions involved matters of public concern. Here, Justice Powell argues, the trial court can award punitive damages without considering malice at all because -- a new distinction -- the Vermont company's credit rating is not a matter of public concern.

As Justice Brennan observes in his dissent, the court has offered almost no guidance regarding a definition of that term. Can you now conclude that all credit ratings, at least, are not matters of public concern? Not at all. Justice Powell, in a footnote, says that it depends "on whether the report's 'content, form and context' indicate that it concerns a public matter." That's little more than an invitation to further litigation.

Readers hardly need to be reminded that we, as a newspaper, have a direct interest in the law of libel. But the impact of these decisions is not limited to the publishing business. They try to balance two basic rights of citizens -- the right of access to the widest possible flow of information, and the right to protect one's reputation.

One attribute of good law is that it follows clear principles comprehensible to people as they manage their affairs. But as the court struggles with this collision between rights, it is developing a body of law that becomes murkier and less predictable. The Dun and Bradstreet case now introduces a range of new questions about gradations between public and private concerns that will be answered only by further libel suits and opinions for years to come.