Ladele, 47, was threatened with the sack, bullied and 'thrown before the lions' after asking to be excused from conducting civil partnerships for same-sex couples because of her religious beliefs.
But a tribunal agreed that her faith had been ridden roughshod over by equalities-obsessed Islington Council, which had sought to 'trump one set of rights with another'.
The groundbreaking decision could lead to firms facing 'conscience claims' from staff who say their own beliefs prevent them carrying out part of their job.
Thursday's ruling found that Liberal Democrat-run Islington Council in
Speaking afterwards, Miss Ladele said: 'It is a victory for religious liberty, not just for myself but for others in a similar position to mine. 'Gay rights should not be used as an excuse to bully or harass people over their religious beliefs.'
Miss Ladele, who is single, said she was treated like a pariah by colleagues and left in an 'intimidating, hostile, degrading, humiliating or offensive environment'.
She had wept as she told the tribunal how her employers gave her an ultimatum to perform the ceremonies or face dismissal for gross misconduct. 'I was being picked on a daily basis,' she said. She said she felt like she was being 'thrown before the lions', explaining: 'I hold the orthodox Christian view that marriage is the union of one man and one woman for life and this is the God-ordained place for sexual relations.
'It creates a problem for any Christian if they are expected to do or condone something that they see as sinful.'
Her nightmare began in 2004, when she realised that legislation permitting civil partnerships at town halls between gays or lesbians would require her to preside over the ceremonies. Miss Ladele raised her concerns, but was ridiculed. Her boss, Helen Mendez-Child, said her stance was akin to a registrar refusing to marry a black person.
In 2006 Miss Ladele and another, unnamed, Christian colleague were accused of 'discriminating against the homosexual community'.
In May 2007, the council launched an internal disciplinary inquiry into Miss Ladele. Four months later, she was told if she did not co-operate she would be sacked. She took the council to an employment tribunal, claiming discrimination, harassment and victimisation on the grounds of religion or beliefs. The
In its ruling, which could have implications for the administration of the 18,000 same-sex ceremonies conducted every year, the tribunal said: 'This is a situation where there is a conflict between two rights or freedoms. It is an important case, which may have a wider impact than the dispute between the parties.
'The tribunal accepts that it would be wrong for one set of rights to trump another. The evidence before the tribunal was that Islington Council rightly considered the importance of the right of the gay community not to be discriminated against but did not consider the right of Miss Ladele as a member of a religious group.
'Islington Council decided that the service it provided was secular and that the rights of the lesbian, gay, bisexual and transsexual community must be protected. In so acting, it took no notice of the rights of Miss Ladele by virtue of her orthodox Christian beliefs.'
Compensation will be decided in September. There is no limit to the amount that can be awarded for religious discrimination.
The Evangelical Alliance hailed the an employment tribunal’s ruling “a triumph for the place of conscience in public duties”.
Dr Don Horrocks, Head of Public Affairs at the Evangelical Alliance said, "This is an important landmark judgment because it conclusively confirms that where there are competing rights a balance has to be struck which treats the respective rights equally.
“The tribunal made it clear that it would be wrong for one set of rights to trump another This decision underlines that, despite some recent claims to the contrary, freedom of religious conscience must be protected by law in the same way as any other human right and that employers must take a person's religion and belief fully into account when considering policy and action.”
Dr Horrocks urged other local authorities to guarantee the same protection to employees of different faiths in light of Thursday’s ruling. "The demands of conscience and civil duties can and must co-exist,” he said. “We would call on local politicians to take note and live up to the challenge of this benchmark decision. …We commend Lillian Ladele for her bravery in standing up for her faith in such intimidating circumstances.”
In her own comment, an employment lawyer Lisa Mayhew, of Jones Day, said: 'It is a bit of a wake-up call for employers. 'They need to think about whether their instructions and the tasks expected of staff might cause people with religious beliefs more problems than others. It does not have to be religion – this could apply across the spectrum in terms of race, gender or sexual orientation.'
But Ben Summerskill, of gay rights campaign group Stonewall, said: 'Public servants are paid by taxpayers to deliver public services. They shouldn't be able to pick and choose who they deliver those services to.'
Also protesting the ruling, gay rights campaigner Peter Tatchell said the ruling was a "dangerous subversion" and a "violation of human rights".
"Lillian Ladele”, he said “claims she has won a victory for religious liberty. No, she has not. She has won a victory for the right to discriminate…"Public servants like registrars have a duty to serve all members of the public without fear or favour. Once society lets some people opt out of upholding the law, where will it end?"
Condemning the "catastrophic judgment" the National Secular Society said: "This decision appears to show that religious rights trump gay rights and that should leave gay people quaking in their boots."