The Archbishop of York, Dr John Sentamu, is the second highest ranking clergyman in the Church of England. He has chosen to use his influential position to launch an inflammatory attack on the democratic will of the British people and on the human rights of lesbian, gay, bisexual and transgender (LGBT) men and women.

Dr Sentamu, who born in Uganda and fled Idi Amin's dictatorship, has condemned the government over its plans to legalise same-sex civil marriage; insinuating that the prime minister is behaving in a dictatorial manner.

It is, however, Dr Sentamu who seeks to dictate. He wants to impose his personal opposition to gay marriage on a society that overwhelmingly rejects his demand for homophobic discrimination.

The archbishop is unelected and owes his post to patronage, whereas the government has been elected democratically by millions of voters. Moreover, a clear majority of the British people, including many Christians, support same-sex civil marriages. A Populus poll, published in The Times newspaper in June 2009, found that 61% of the public believe that: "Gay couples should have an equal right to get married, not just to have civil partnerships." Only 33% disagreed.

Dr Sentamu rejects the enlightened, progressive public will, in favour of his preferred imposition of homophobic discrimination in law. He is, in essence, a religious authoritarian who opposes equality.

I am no theologian or expert in ecclesiastical matters, but from my understanding of scripture it is not a loving Christian value to demand discrimination against other human beings. To insist that the law discriminate against gay couples and treat them as inferior, second class citizens strikes me as devoid of the love and compassion that is attributed to Jesus Christ in the gospels.

The archbishop's insulting, disparaging attitude towards lesbian and gay couples is evidenced by the way he dismisses loving, committed, loyal same-sex civil partnerships as mere "friendships."

He would never describe heterosexual couples in love, whether they were married or unmarried, as mere friends.

Right from the outset of the debate about marriage equality, Dr Sentamu seems to have got the wrong end of the stick. The government is proposing to legalise same-sex marriages in register offices only. This will not affect churches or other places of worship. The archbishop has no valid grounds for objecting to civil registrations that will ensure marriage equality for all couples. It does not impact on his religious domain.

Dr Sentamu comes across as intolerant and out of touch. His stance colludes with homophobia. It brings shame and dishonour to the Church of England. Even many Anglicans are likely to be repulsed by his advocacy of anti-gay discrimination. They, and most non-religious people, will see his stance as further evidence of the bigotry that burns in hearts of many so-called Christian leaders.

The archbishop's justification that it is vital to demand the preservation of the tradition and history of exclusively heterosexual marriage is very similar to the arguments that were in the past used by the church to justify slavery, colonialism and the denial of votes to women. Appealing to past injustices to preserve current injustices cuts no ice with most people.

Archbishop Sentamu has long been accused of collusion with homophobia. When the Anti-Homosexuality 'Kill the Gays' Bill was first introduced in the Ugandan parliament, Sentamu took ages to respond, despite the fact that he is from Uganda and was being urged to speak out against the proposed death penalty for repeat homosexual offenders. He did eventually condemn the death sentence provision, but not the Bill itself or its other draconian clauses.

A decade ago, Dr Sentamu was involved in the perceived cover up of the homophobic abuse and assaults on Damilola Taylor, which occurred shortly before the young boy was murdered in November 2000. These attacks, and the possibility of a homophobic motive, were not even mentioned in Sentamu's 2002 report into the killing.

Regardless of his hostility to marriage equality, the Equal Love campaign is confident that Britain will eventually overturn the twin legal bans on same-sex civil marriages and opposite-sex civil partnerships. We've already succeeded in helping persuade the government to commit to the legalisation of gay civil marriages before the next election in 2015; although David Cameron is sadly, and very oddly, insisting that the ban on heterosexual civil partnerships must remain.

To ensure that we overturn both discriminations, Equal Love currently has an appeal against the twin bans under consideration by the European Court of Human Rights.

We argue that banning same-sex couples from civil marriages and opposite-sex couples from civil partnerships is illegal discrimination, contrary to Articles 8, 12 and 14 of the European Convention on Human Rights. Owing to the backlog of cases, it may take another three years to get a judgement. But we are quietly confident that we can win equality for all, despite Archbishop Sentamu's demand for continued discrimination.

* For more information about Peter Tatchell's human rights campaigns and to make a donation: www.petertatchell.net