Still, the unusual product-liability charges brought by the plaintiffs here are a source of new concern to record companies already worried about the recent arrest of members of the 2 Live Crew rap group on obscenity charges and efforts to put warning labels on recordings deemed to be harmful or obscene. If successful, the product-liability suit would force record companies to screen lyrics or face the possibility of having to pay huge punitive damages in similar cases.

In at least three previous incidents, in California, Georgia and New Jersey, fans of heavy metal have killed themselves after listening to the album ''Suicide Solution'' by the rock singer Ozzy Ozbourne, another artist who has recorded for CBS. The California case was dismissed before coming to trial when a court ruled that song lyrics were protected by the free speech provisions of the First Amendment. The Georgia case is still pending, and heavy metal is no longer a factor in the New Jersey case.

Subliminal Messages

In this case, however, lawyers for the plaintiffs argue that the young men were driven to shoot themselves by the subliminal messages the musicians placed in the music, such as ''Let's be dead'' and ''Do it.'' Though he has yet to decide whether the Judas Priest recordings had such material, Judge Jerry Carr Whitehead has ruled that such subliminal messages were not a form of speech and therefore were not covered by First Amendment protections.

Lawyers for the Belknap and Vance families have contended that some subliminal messages were masked by being played backward in songs, an argument Ms. Fulstone urged Judge Whitehead to dismiss as having no scientific basis. ''The courtroom is no place for reveries about the unknown capacity of the human mind'' to absorb such material, she said.

The essential facts of the case are not in dispute. After smoking marijuana and drinking beer while listening to songs from several Judas Priest albums, Mr. Belknap and Mr. Vance agreed to a suicide pact, went to a nearby church playground, and shot themselves in the head with a 12-gauge shotgun.