Here’s one sign that the Federal Communications Commission is taking the occasional swear word too seriously: An f-bomb from Cher at the 2002 Golden Globes has been the subject of a decade of wrangling between the agency and the Fox network — and two trips to the nation’s highest court.

On Thursday, the Supreme Court ruled that the FCC shouldn’t have reprimanded Fox for Cher’s outburst or for profane comments by Nicole Richie on a Fox broadcast the following year, nor should it have fined ABC because an “NYPD Blue” character’s buttocks were visible for seven seconds in 2003. The agency had tightened up its policies to forbid such incidents without giving the broadcasters fair notice, the court ruled. Yet the justices sidestepped the broader question of whether the FCC was being too stringent to begin with.

Broadcasters are subject to FCC rules because they use the public airwaves, but the boundaries of indecency have rarely been clear. In 1978, the Supreme Court set a standard of sorts, when it ruled that a radio company could be punished for an afternoon broadcast of comedian George Carlin’s famous “Filthy Words” routine. Yet public standards have evolved, the broadcast world has fragmented, and new networks — even whole new categories of entertainment — have come into the world. (Strikingly, Justice Anthony Kennedy’s opinion refers to “the singer Cher” and “the singer Bono,” but merely “a person named Nicole Richie.”)

Broadcasters are wary enough about offending their audiences to merit some benefit of the doubt. And the FCC can prevent the public broadcast of graphic sexual imagery without cracking down hard on Carlin’s seven dirty words.