A gay woman wrongly deported from the UK five years ago has been told she can return in a landmark court ruling that could open the door to thousands of similar challenges.

In an unprecedented case, the Home Office has been ordered to facilitate the return of a Ugandan asylum seeker after the High Court ruled the decision to reject her claim was unlawful.

The 25-year-old woman arrived in the UK in 2011 and claimed asylum on the basis that she was a lesbian and would be at risk of persecution in Uganda. She was refused and removed in 2013 on the grounds that the Home Office did not believe she was gay.

But a High Court judge has now ruled the government’s decision to refuse her claim was reached by an unfair process which did not give her sufficient time to obtain evidence to support her case.

The woman is one of thousands of asylum seekers whose immigration cases were decided under the Home Office’s “detained fast-track” system, which was introduced in 2005 and came to an end in 2015 after the High Court ruled that it was “structurally unfair”. Her case is the first successful appeal allowing a claimant to return to the UK.

Windrush generation: threat of deportation from UK Show all 15 1 /15 Windrush generation: threat of deportation from UK Windrush generation: threat of deportation from UK The ex-troopship 'Empire Windrush' arriving at Tilbury Docks from Jamaica, with 482 Jamaicans on board, emigrating to Britain. Getty Windrush generation: threat of deportation from UK Jamaican immigrants being welcomed by RAF officials from the Colonial Office after the ex-troopship 'Empire Windrush' landed them at Tilbury. PA Windrush generation: threat of deportation from UK Alford Gardner who arrived in Britain in 1948 on the first Windrush ship to dock in Tilbury, Essex, speaking at his home in Leeds PA Windrush generation: threat of deportation from UK Alford Gardner in Leeds shortly after he arrived in Britain in 1948 on the first Windrush ship to dock in Tilbury, Essex PA Windrush generation: threat of deportation from UK Gardner was 22 years old when he boarded the ship in Kingston, Jamaica, with his brother Gladstone before they and hundreds of Caribbean migrants called on to rebuild post-war Britain disembarked the ship in Tilbury Docks PA Windrush generation: threat of deportation from UK Alford Gardner (right), during his RAF service in 1947 PA Windrush generation: threat of deportation from UK The son of Ruth Williams, a Windrush-generation immigrant, wants to the leave the country after threats of deportation. According to his mother, Mr Haynes applied for British citizenship in 2016 but was rejected, despite Ms Williams having lived in the UK almost permanently since arriving from St Vincent and the Grenadines in 1959. Ruth Williams, 75, said she felt "betrayed" by Britain after the Home Office twice turned down applications for her 35-year-old son, Mozi Haynes, to remain in the country. Ms Williams is understood to have cancer and said she relies heavily on her son for support. PA Windrush generation: threat of deportation from UK The British liner 'Empire Windrush' at port in 1954. Getty Windrush generation: threat of deportation from UK Ruth Williams, 75, with her British passport. "I feel betrayed and a second class citizen in my own country," she said. "This makes me so sad and the Home Office must show some compassion. "I am unwell and almost 75, I live on my own and I need my son to stay here. I need my family around me and I can’t face being alone. He has applied to the Home Office and been refused twice." PA Windrush generation: threat of deportation from UK From the top, hopeful Jamaican boxers Charles Smith, Ten Ansel, Essi Reid, John Hazel, Boy Solas and manager Mortimer Martin arrive at Tilbury on the Empire Windrush in the hope of finding work in Britain. Getty Windrush generation: threat of deportation from UK Jamaicans reading a newspaper whilst on board the ex-troopship 'Empire Windrush' bound for Tilbury docks in Essex. Getty Windrush generation: threat of deportation from UK After half a century in Britain, Anthony Bryan decided it was time to go abroad. But the decision set off a nightmare that saw him lose his job, detained twice and almost deported to Jamaica. AFP/Getty Windrush generation: threat of deportation from UK Jamaica-born Anthony Bryan poses outside his home in Edmonton, north London. Now 60 and a grandfather, Bryan thought the issue could be resolved swiftly, as he legally moved to Britain with his family as part of the Windrush generation of Caribbean migrants after World War II. In 1948, the ship Windrush brought the first group of migrants from the West Indies to help rebuild post-war Britain, and many others followed from around the Commonwealth. A 1971 law gave them indefinite leave to remain, but many never formalised their status, often because they were children who came over on their parents' passports and then never applied for their own. AFP/Getty Windrush generation: threat of deportation from UK Three Jamaican immigrants (left to right) John Hazel, a 21-year-old boxer, Harold Wilmot, 32, and John Richards, a 22-year-old carpenter, arriving at Tilbury on board the ex-troopship 'Empire Windrush', smartly dressed in zoot suits and trilby hats. Getty Windrush generation: threat of deportation from UK Newly arrived Jamaican immigrants on board the 'Empire Windrush' at Tilbury in 1948. Getty

The fast-track system, which aimed to make asylum decisions within two weeks and required that people were kept in detention during the process, had a 99 per cent rejection rate. Many on the fast track were from countries experiencing conflict or violence, such as Afghanistan and Sri Lanka.

The court ruled in 2015 that the system did not allow enough time for lawyers to take instructions, prepare statements, translate documents and obtain evidence.

Lawyers and campaigners said the latest ruling could pave the way for thousands of similar challenges from people who were removed under this system.

Bella Sankey, director of Detention Action, said the judgment marked an “important first step in putting right a mass wrong”.

“Just because the Home Office has managed to unlawfully remove people years ago doesn’t mean it has extinguished their rights. Our independent judiciary will rightly use its discretion to remedy injustice, including ordering that banished asylum seekers are returned,” she said.

“Just as with the victims of the Windrush scandal that followed, many thousands may have been unlawfully and wrongfully removed.”

Legal author Alex Schymyck warned there remained “big practical barriers” to getting cases heard, as lawyers would need to re-establish contact with clients no longer in the UK.

Campaigners also raised concerns that, despite “overwhelming” evidence that the fast-track process was harmful, the Home Office was “repeatedly” trying to reintroduce a similar system.

The Tribunal Procedure Committee, which sets the rules governing asylum and immigration cases, last month rejected government proposals to introduce an accelerated process for immigration appeals that would limit the timeframe for decisions to 25 working days.

But Pierre Makhlouf, assistant director at Bail for Immigration Detainees (BID), said that despite warnings, the government continued to attempt to reintroduce these rules.

“The tribunal has rejected the Home Office’s proposals, but the department has shown that it will repeatedly try to introduce such processes, despite the overwhelming evidence that they are harmful and create obstacles to justice,” he said.

“We’re aware that several thousand people went through this process, and the fact that it was an unfair and unjust process indicates that thousands of people have been wrongly served by the justice system.

“But most people who have been removed will have no access to a legal representative to be able to bring forward a challenge.”

Labour’s shadow home secretary, Diane Abbott, said: “It is clear that the government has a tick-box exercise to treating the most vulnerable asylum seekers. It isn’t working and is wrongly deporting people that should have a fair appeal and may even have the right to remain.”

Sir Ed Davey, home affairs spokesperson for the Liberal Democrats, said the fact that thousands of asylum seekers may have been wrongly removed was “yet another stain on the Home Office’s record”.

He added: “The fact that we know for definite that just one individual was wrongly removed from our country should be enough to shame this Tory government into taking immigration away from the Home Office.”