It wasn’t a moving coming out scene, but it was bracing. “I’m sorry Dad, I’m queer,” Jeremy Wolfenden told his father Sir John, later Lord, Wolfenden. “Balderdash,” replied his father. “Don’t be flippant with me.”

There have been quite a few programmes to mark the 40th anniversary of the decriminalisation of homosexuality, the best – both old and new – on BBC Four. Julian Mitchell’s Consenting Adults was the sharpest and funniest, telling three stories: the bizarre course of the committee Lord Wolfenden oversaw that ultimately led to the reforming 1967 Sexual Offences Act; a self-contained story of ill-fated love and betrayal featuring a baker and a wide boy enmeshed by the iniquitous laws of the time; and, most fascinatingly, the story of Lord Wolfenden and his gay son.

If Jeremy’s homosexuality had been exposed while his father was leading such a sensitive committee, it would have proved explosive; the Guy Burgess scandal and the show trial of Lord Montagu of Beaulieu and Peter Wildeblood were blazing across the papers. Jeremy was old-school flamboyant: beatniky clothes, excessive boozing, overtly gay; he revelled in self-exposure. Sir John begged him to be discreet as the committee looked into the laws on homosexuality and (less well known) prostitution. Jeremy tried and failed to blackmail him: “I’ll watch my step if you recommend a change in the law.”

At the outset, concerned about propriety and inspired by biscuits, Sir John wondered if he should refer to homosexuals as “Huntleys” and prostitutes as “Palmers”. He thought homosexuality “morally repugnant” but believed the law could not legislate for private behaviour. This wasn’t enough for the foaming mouths of some of the committee, who saw homosexuality as a contagion.

Charles Dance was a prickly Wolfenden. He was grave yet dry; evident as he geekily observed the model of new buildings planned for the University of Reading where he was vice-chancellor, and as he chivvied his wife (Samantha Bond) along with the gardening. Just across from their house, lights flickered in the bushes: gay men lighting each other’s cigarettes and policeman’s torches flushing them out of the foliage – a perpetual, pointless chase.

Mitchell, responsible for the play, and screenplay, Another Country, is a master of big issues and small lives, colouring character with glinting mischief. A dry civil servant cut through the moralising cant of committee members. While Jeremy preached (“Queers can love each other the same as straights, Mum”) he also cruised labourers and his new university dorm-mate.

Richard Curson Smith’s direction was playful. In one great scene Jeremy set himself on fire (after dropping off, sloshed), woke up, extinguished the flames, then lit up again. Smoky jazz drifted languorously throughout, the musical equivalent of an arched eyebrow. When the committee took shape, each member appeared ghostlike on their chair. Mark Gatiss stole a whole scene as a policeman giving evidence to the committee: “Americans like using the mouth.” Alfred Kinsey, the American sexologist, caused tea to be spilt whenhe reported that over a third of men had had gay sex “leading to orgasm”.

After frustrating exchanges about the age of consent (eventually settled upon as 21, to appease the moralisers and the Church), Wolfenden’s report was put on ice. Published in 1957, the law would change ten years later and even then an equal age of consent was won ultimately only in 1998. This season of anniversary programmes reminds you how modern and convulsive the fight for gay equality has been.

Jeremy eventually became a journalist and there was a wonderful, moving moment when he left for Moscow to be a foreign correspondent. Lord Wolfenden tenderly said “Goodbye darl-” then corrected himself gruffly, “Bye old chap.”

Jeremy died, aged 31, of an alcohol-related illness. His father died in 1985 just as Aids tightened its grip and before Margaret Thatcher constructed the hideous Section 28 because, as she said, children were being taught “they have an inalienable right to be gay”. Well they do, we all do, thank goodness, and her bigotry and despicable policy-making are (hopefully) permanently consigned to the past. Thank you, Lord Wolfenden. As Jeremy, in one of his rare sober moments, told his father: “You did the right thing against your own inclination. That makes you an admirable man.”

Out of the box

Noticed a theme on ITV1? 9.25 The Jeremy Kyle Show; 10.30 This Morning; 12.30 Loose Women; 3pm Alan Titchmarsh Show; 5pm That Antony Cotton Show. The channel is awash with inane chat. The brief for Titchmarsh is for him to be Yorkshire-blokey, the housewives’ favourite. Hmmm. Theother day he joked Heather Mills McCartney didn’t have “a leg to stand on”. Alan, don’t do “edgy”. It’s creepy. He agonised that the media was stoking the flames of the Amy Winehouse saga (this in the middle of a ten-minute discussion of it). And he and some WI ladies talked about bras and pants. A bizarre hour, but at least the studio has been designed in Titchmarsh’s honour with empty urns and some horrible topiary.

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