A lesbian expatriate fending off Hong Kong authorities in a final court appeal for her spousal right to remain in the city has picked up strong backing from major banks, law firms and an international NGO.

Fifteen financial institutions, 16 law firms and human rights group Amnesty International were seeking to have a say in the government’s final appeal against QT, which is set to be heard at the Court of Final Appeal on June 5, according to a statement on Wednesday by Vidler and Co, the law firm representing her.

The woman, who followed her partner SS to Hong Kong, won in a lower appeal court last September to have their civil union relationship formed in Britain recognised in the city for the purpose of a dependent visa.

The court decision upended the Immigration Department’s practice of granting such visas only to heterosexual married couples. Following the ruling, the government lodged a final appeal.

Rather than fighting the authorities alone, Vidler and Co announced on Wednesday that a host of organisations had lent support to QT, whose identity is protected by the courts.

Her lawyer Michael Vidler told the Post: “QT welcomes the applications for intervention from such a renowned and respected international human rights NGO and such a broad group of the global financial institutions and law firms in Hong Kong.”

His firm added that it was notified about the parties’ move last month. It said the institutions and law firms had substantial business, operations and workforces in the city, and they would seek to give the court “a more rounded picture”.

If approved, these parties are expected to present their arguments in court via their lawyers, which will likely include an explanation of how the restricted immigration policy has had an impact on them.

The institutions include Credit Suisse, Goldman Sachs and Morgan Stanley. Amnesty International has also confirmed its involvement.

But the 32 bodies still require the court’s approval before they can get involved.

This is not the first time major banks have sought to be a party to the case.

At the earlier appeal court level, 12 of the 15 institutions in the present application requested to have their voices heard. But their motion was rejected by the Court of Appeal.

QT, a British citizen, entered a civil partnership in England just months before she moved to Hong Kong in 2011 with SS, who had been offered a job in the city.

But after her arrival, QT’s application for a spousal visa was denied, prompting her to apply for a judicial review.

She lost at the Court of First instance, but won at the Court of Appeal. The higher court ruled that the Immigration Department’s refusal amounted to indirect discrimination.

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