Hundreds of trafficking victims trying to start new lives in Britain have suffered as a result of a “secret internal policy” operated by two home secretaries, a campaign group has alleged during a High Court hearing.

Asylum Aid said that from early 2022 to April 2023 the Home Office operated a “secret policy” to frustrate the right to remain of at least 1,600 confirmed victims of trafficking and modern slavery.

Government lawyers dispute the claims.

The allegations were made during a High Court damages fight involving an asylum-seeker and the Home Office, relating to periods when Priti Patel and Suella Braverman were in office.

Dame Priti Patel was in office when the ‘secret policy’ was in operation, the campaign group says (Stefan Rousseau/PA)

Lawyers representing the asylum-seeker, who is being supported by Asylum Aid, have told a judge that a “serious misuse of power” has been exposed.

The man, an Albanian in his 20s who has not been named during the litigation, says, as a result of the “secret, unlawful policy”, he was denied the right to leave to remain in Britain for more than a year.

He claims that denial of the right to leave to remain breached his human rights – and he wants damages.

Ministers are fighting the claim and a barrister leading the Home Office legal team told Mr Justice Lane on Thursday that the issue was “delay” not “secret” policies.

Lawyers representing the man outlined allegations in a written argument.

Chris Buttler KC and Zoe McCallum told the judge: “This claim exposes a serious misuse of power.”

They said there was a policy granting modern slavery victims leave to remain in Britain – in accordance with a European convention against trafficking.

The two lawyers said, in October 2021, a High Court judge’s decision required the Home Office to grant recognised modern slavery victims leave to remain where they had a pending asylum claim.

They said that decision created a right to leave to remain to a “class of victim of modern slavery” not hitherto thought by the Home Office to have such a right.

But they alleged that there had been a “secret internal policy” telling officials not to grant the right to leave to remain created by that decision.

Outside court, a spokeswoman for Asylum Aid said that evidence had been garnered from documents disclosed during the litigation.

Cathryn McGahey KC, who is leading the Home Office legal team, said: “This case is about delay.

“It is not a case about secret or unpublished policies.”

Ms McGahey added, in a written case outline, that the man had not suffered “any significant detriment as a consequence of the pause in decision-making”.

She said he had continued to receive “state support in the form of housing, education, medical care and state benefits” – and told the judge that his claim should be dismissed.