Ralph Nader is the very model of a public citizen vigorously exercising his free-speech rights around the clock. Case in point: a while ago, he lashed out at the Educational Testing Service (the source of the dread Scholastic Aptitude Tests that determine who gets into college and where), thundering: "ETS's claims to measure aptitude and predict success are false and unsubstantiated, and can be described as a specialized kind of fraud."

But when Nader himself was vigorously criticized in similar terms by a little-known right- wing columnist, this champion of robust debate on public issues chose to punish his critic with a million-dollar libel suit. The case has been going on since 1975, and only now is about to be scheduled for trial.

>In the meantime, the defendant, Ralph de Toledano, has lost his life savings in paying for lawyers and other court costs during the preliminary legal skirmishes. Whether Nader actually wins the case or not, he sure has had his revenge.

You probably have not heard of Nader v. de Toledano because the press has virtually ignored the suit, despite its ominous First Amendment implications. Nor have any of the press' legal defense forces come to de Toledano's aid. The reason, as I have discovered in a series of interviews, is that de Toledano is considered too right-wing to bother with.

Not being as "respectable" as George Will or James Kilpatrick, de Toledano isn't worth fighting for. After all, he's not a regular on public television.

This is how it all began. In January 1975, de Toledano wrote in his column that then senator Abraham Ribicoff had "devoted some 250 devastating columns of the Congressional Record to demonstrate conclusively that Nader falsified and distorted evidence" to make his case against the General Motors Corvair automobile.

De Toledano was referring to a huge staff report for a Ribicoff subcommittee that claimed, after two and a half years of extensive research, that Nader had not made his case against the Corvair. But did the report show that Nader had falsified and distorted evidence? Or was this an act of libel by de Toledano?

As a public figure, Nader can win this libel suit only by proving, with convincing clarity, that de Toledano is guilty of "actual malice"--that is, he knew what he wrote was false or he went ahead and printed that comment with reckless disregard for whether it was false or not.

It was a long, complex report, and, as one judge said during these seven years of preliminary battles, "de Toledano's interpretation of the whole of the staff report . . . should be protected and privileged as a rationally defensible choice among a range of interpretative alternatives."

It's not as if de Toledano had taken a report celebrating Citizen Nader and invented a contrary conclusion. Sure, he was harsh in his interpretation, but so has Nader been. If Nader felt that abused, why didn't he use his many channels of public expression to rebut his critic instead of hauling him into court?

To paraphrase Harry Truman, if you can't take just a little bit of the heat that you yourself are stoking all the time, then you ought to get out of the arena. Furthermore, what damage--monetary, psychic or reputational--has Nader suffered from that single de Toledano paragraph?

Or was this meant to be a lesson to other journalists that Saint Nader is to be considered immune from attack?

>The first court that had the case threw it out. The judge found no clear and convincing evidence of "actual malice" on de Toledano's part, but a court of appeals said a jury ought to decide that question. The Supreme Court declined to review the court of appeals decision despite the fact that the high court had said in 1967 that the constitutional guarantee of freedom of the press is "not for the benefit of the press so much as for the benefit of all us, (for a) broadly defined freedom of the press assures the maintenance of our political system and an open society."

Now that freedom is up to a jury, and juries these days increasingly tend to view the First Amendment as an irritant that should be curbed.

Well, Ralph de Toledano, who can no longer afford a lawyer, now has two pro bono paladins--Richard Schmidt Jr., general counsel of the American Society of Newspaper Editors, and Arthur Hanson, general counsel emeritus of the American Newspaper Publishers Association. They're acting on their own because, says Schmidt, "this guy hasn't got a dime, but that doesn't mean he shouldn't have a defense."

Of course, not only de Toledano is being defended. So is the First Amendment, which, come to think of it, has often been penniless itself.