Human rights campaigner Peter Tatchell said today he would be happy to testify in defence of the Christian housing manager demoted for expressing his views on gay marriage.

Adrian Smith was forced to accept a more junior position, and had his pay cut by £14,000 a year, after calling religious ceremonies for gay couples “an equality too far” on his personal Facebook page.

His employer, the Trafford Housing Trust, found him guilty of misconduct but the severity of the punishment provoked criticism from several areas.

Writing in the Huffington Post, Mr Tatchell said: “I am backing his bid for reinstatement and I’m prepared to testify in his defence. Strange but true.”

He went on: “Adrian Smith made his comments in his own time on his own Facebook page, which is not viewed by the general public. He expressed an opinion. He did not personally discriminate against anyone. There is no evidence that he has treated any of his gay housing clients adversely.

“Smith voiced his opinion in a calm, non-abusive manner. He was not threatening or intimidating.

“His only possible misdemeanour is that he made his comments on a Facebook page where it mentions that he works for Trafford Housing Trust, which is allegedly contrary to THT regulations. This is hardly a major crime. It certainly does not warrant the disproportionate punishment inflicted upon him.”

He added: “If a gay employee was treated this harshly by a Christian organisation for writing pro-gay comments on their personal Facebook page, there would quite rightly be an outcry and accusations of homophobia.

“Why, then, are some lesbian and gay people supporting such a harsh penalty for Adrian Smith?”

When questioned by a friend about the move, Mr Smith had added to his comment on the social networking site: “I don’t understand why people who don’t believe in Christ would want to get hitched in church.

“The Bible is quite specific that marriage is for men and women. If the state wants to offer civil marriages to the same sex then that is up to the state; but the state shouldn’t impose its rules on places of faith and conscience.”