HE is one of Britain’s most successful television dramatists, yet Tony Marchant has been told by the BBC to prove himself worthy by sitting an elementary test about how to portray “goodies and baddies”.

Marchant, a Bafta-winning writer, is the latest big name to fall foul of the BBC’s spiralling compliance culture intended to prevent a repeat of editorial scandals such as the Sachsgate affair involving Russell Brand and Jonathan Ross.

Critics believe the new regime is being enforced with such zeal that it risks backfiring and stifling creativity.

Producers recently tried to get the phrase “Oh, sweet Jesus” removed from a script of My Family, the hit BBC1 comedy show, for fear of causing offence. They were forestalled only by a cast rebellion. A forthcoming audio adaptation of Doctor Who dropped a reference to a character being drunk, partly because it could encourage children to hit the bottle. The character was instead described as being merry and cheerful.

Last week, BBC2 viewers were solemnly warned by a continuity announcer that an Alan Whicker programme contained “scenes of bullfighting” — even though it was broadcast at 11.20pm, well past the watershed. One director said: “The BBC is effectively policing itself out of existence because it does not want to offend or upset anyone.”

Another star said the broadcaster had become so censorious that he felt as if he was working for the “Taliban Broadcasting Corporation”.

Marchant, 50, who wrote the award-winning series Holding On for the BBC and The Mark of Cain for Channel 4, was required to sit the “Safeguarding Trust factual drama interactive module” last month as he was completing his new BBC1 programme, Garrow’s Law, which starts tonight.

He now has a certificate that congratulates him on passing the test and provides helpful tips such as: “Don’t oversimplify the ‘goodies’ and the ‘baddies’ ... the truth is rarely as cut and dried as this.”

He is further reminded that “tone of voice and facial expression can significantly alter what an audience infers about a character”.

Marchant, a winner of Bafta’s Dennis Potter award for outstanding contribution to TV drama, said: “The module is a complete nonsense and proof that the compliance culture is out of control at the BBC. I was baffled when I was asked to do it and still can’t see the point of it.”

The BBC Trust, the corporation’s watchdog, demanded tougher compliance procedures after the Queen was misrepresented in a promotional trailer in 2007. The broadcaster launched a further crackdown after Ross and Brand left obscene messages on the phone-answering machine of Andrew Sachs, the veteran actor, during a Radio 2 show last year.

All BBC staff, including Mark Thompson, the director-general, and any independent companies who work for the broadcaster, are obliged to sit the Safeguarding Trust course.

Last week the BBC was criticised for removing an episode of This Week, the late-night political show presented by Andrew Neil, from its iPlayer service.

Neil had likened his co-hosts, the black MP Diane Abbott and Michael Portillo, the former cabinet minister, to a chocolate HobNob and a custard cream, which BBC bosses are believed to have feared would be deemed racist.

Although the BBC Trust has been keen to appear tough in the face of each new editorial scandal, critics believe it has been inconsistent in meting out punishment.

It recently upheld a complaint against Frankie Boyle, a panellist on Mock the Week, the BBC2 comedy quiz, in relation to comments about Rebecca Adlington, the Olympic swimming champion.

Boyle’s description of Adlington as “very dirty” and resembling “someone who’s looking at themselves in the back of a spoon” was judged to be humiliating and offensive.

However, the trust failed to uphold a second complaint against Boyle in relation to a sexual joke about the Queen.

Boyle, who has since quit the programme, said: “It is disheartening. Who are these people? What authority do they have to judge comedy?”

Hugh Bonneville, the actor who starred alongside Julie Walters in BBC2’s Filth: The Mary Whitehouse Story, said it was time to return to common sense. “I now detect a creeping self-censorship in the television scripts I am given to read,” he said. “I remember in the light of the Queengate affair the producer of the Mary Whitehouse programme saying the compliance unit wanted him to go through the script pointing out which bits actually happened and which were dramatic invention.

“Whatever next? Do you put up a warning at the beginning of the programme telling the audience that Julie Walters is not Mary Whitehouse?”

Sir John Tusa, a former managing director of the BBC World Service, believes the compliance regime needs to be overhauled. “I recently met a senior figure in the BBC who admitted that the compliance unit is a waste of time which distracted from serious activity,” he said.

A BBC spokesman said: “We have taken action to strengthen parts of our guidelines after a few unacceptable failures in editorial judgment and compliance, but creative risk-taking remains alive and well.”

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