Aiming for "truth in advertising," two public-interest-minded groups yesterday petitioned the Federal Communications Commission (FCC) to require that the identity of buyers of television campaign commercials be made clear to viewers.

Arthur J. Kropp, president of People for the American Way, said, "There is a concerted attempt to confuse or deceive the voters into not knowing" who is sponsoring an ad. He said that is one reason negative ads are so effective.

Under federal rules, candidates can qualify for a special low advertising rate by putting a candidate likeness and statement of sponsorship in the ad. The judgment of whether the candidate's likeness is "identified or identifiable" is left to broadcasters. "It's a regulatory loophole you could drive a camera van through," said Andrew Jay Schwartzman of the Media Access Project. "Candidates are using every technical trick to exploit it."

The petition states that too often the candidate identification is so tiny and appears so briefly that it is meaningless. The petition asks that the FCC set guidelines for minimum size and duration to guarantee clarity. The petition does not address ad content.

"We're not out to ban attack ads," Kropp said. "But the law demands that candidates take ownership of their own campaign spots."