Campaign Negatives

STEVE FORBES'S hard-punching TV spots have revived the perennial question of just how effective such attack ads are. The standard answer - and Mr. Forbes's rise in the polls has done nothing to alter it - is that they are quite effective.

Forbes campaign staffers argue that only about half their man's televised advertising is ''negative,'' zeroing in on opponents. But that's still quite a volume, given the TV blitz the candidate's personal fortune supports.

Of course Forbes isn't alone in this tactic. Messages intended to tear down opponents, rather than showcase one's own views, are a mainstay of American political life. They extend back to the republic's earliest years.

Politics is competition, after all, and it sometimes gets rough. Students of the political process point out, moreover, that ads aimed at the other side can serve the public by pointing out shortcomings that candidates try their best to conceal. It's worth remembering, also, that ostensibly positive ads, promoting a candidacy, aren't immune to being one-dimensional and deceptive.

The issue isn't really negativity, per se, but fairness and truth. It's standard campaign procedure to wrap a 30-second spot around one item from an opponent's record - classically, a tax hike or the release of a dangerous criminal - minus any context. But is it fair? Ultimately, voters decide, with some help from journalists committed to impartially assessing the truth and fairness of campaign advertising.

Candidates are well aware that attack ads can boomerang and slap their originator with a ''negative.'' Before the month's out, we'll see if that has happened to Steve Forbes. At the least, his early, massive helping of TV ads may whet the public's appetite for something more substantial come next fall.