OFCOM ordered the BBC to pay 150,000 pounds ($219,000) — the highest fine ever levied on the BBC for a single incident — for an on-air radio routine last year in which Brand and Ross left recorded messages for Andrew Sachs joking about how Brand had sex with the actor's granddaughter.
The two later laughed that Sachs might hang himself as a result of the news.
The calls made during Brand's radio program to Sachs — best known for playing Spanish waiter Manuel in the 1970s program, "Fawlty Towers" — drew thousands of complaints.
Brand resigned after the incident, and Ross, who has his own television program on the BBC, was suspended without pay for 12 weeks. Two senior BBC executives also resigned over the scandal.
OFCOM said in a statement that two broadcasts, the one involving the stunt and a follow-up program that referred to the incident, were gratuitously offensive, humiliating and demeaning.
The regulator said no senior manager listened to the initial recorded program in its entirety before broadcast and there was a failure to obtain the consent of Sachs or his granddaughter.
The BBC reiterated in a statement Friday that the "material should never have been broadcast and we apologized unreservedly for that."
Ross and Brand are known for pushing the boundaries of good taste. Brand wrote a memoir recounting his drug and sex addiction and called President George W. Bush "that retarded cowboy fellow" while hosting MTV's Video Music Awards.
The case is reminiscent of the antics of American "shock jocks" such as Don Imus, who was fired from MSNBC and CBS Radio for making racist and sexist comments about a women's basketball team.
The BBC case was closely followed in Britain partly because the salaries of BBC personalities are paid by the public. The BBC receives most of its funding through a license fee of almost 140 pounds ($204) a year levied on homes with television sets.
Trust in the BBC also has been undermined by other scandals in recent years, including one in which a BBC executive resigned over the editing of footage that wrongly implied Queen Elizabeth II had walked out of a portrait sitting with photographer Annie Leibovitz.
In other cases of BBC audience deception, contest results were faked or recorded programs were presented as though they were live.
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