Lord Browne of Madingley, the disgraced former chief executive of BP, is now out as a gay man, but it is an admission he was so keen on keeping private that he was prepared to commit perjury.

At 59, the man once in command of Britain’s second-most valuable company, still felt that his “sexuality was a personal matter, to be kept private”.

It was those few words that have caused a stir over the past two days in the City. Managing directors at the world’s biggest banks, law firms and accountancy firms and chief executives of FTSE 250 companies have not been, for a change, chasing deals but engaged in a spot of introspection.

They have all been sent on diversity training courses over the past three years, ever since new laws came into force extending anti-discrimination rights to gays and lesbians. They should feel comfortable about working with gay or straight, white or black, Christian or other.

But away from the prying eyes and ears of their human resources and in-house lawyers, City and business executives will tell you they sympathise with Lord Browne. They know the homophobic innuendos that persist in the coffee room or at the bar after work. There is pity, but as they discuss the latest gay discrimination case they snigger, too, complicit in the anti-gay atmosphere that still lingers in the workplace.

City firms have to sign forms declaring that they have a diversity policy before winning clients. But many in the City feel that it is a charade of box-ticking that will end only when chief executives proudly turn up to office functions with their same-sex partners.

Lord Browne was destined for a bank, Goldman Sachs, and a $500,000-a-year job as head of its audit committee, but according to a source at the bank that job is no longer “tenable”, not because of his sexuality but because he lied under oath.

In January, Goldman Sachs was ranked among the top three City firms for being Britain’s top employer of lesbian and gay staff.

Goldman, with Lloyds TSB and KPMG, raced up the leaderboard in the latest annual workplace equality index drawn up by Stonewall, the gay activist group, which ranks the top 100 gay-friendly employers in all businesses. Goldman took eighth position overall, a rise of 20 places, to rank alongside KPMG.

There have been few gay discrimination legal claims to make the light of day. “Often it is in the interests of both parties for deals to be done,” Toni Lorenzo of Lewis Silkin, the law firm, said.

Deutsche Bank settled a claim two years ago from Sid Saeed, a former analyst, in which the bank was accused of allowing a litany of comments, the tamest of which included “queer boy” and “mincer boy”.

HSBC is due back in the employment tribunal this year for a retrial of its conduct in the investigation of an allegedly indecent act in the company showers by Peter Lewis, its gay former head of global equity trading. HSBC executives referred to gays as “nonces”. If men from Britain’s largest firm used that term, the former boss of BP is right to want to keep his sexuality private.

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