Transport Secretary Louise Haigh has admitted she pleaded guilty to a criminal offense relating to a police investigation into a mobile phone she claimed was stolen.

She admitted that ten years ago, she told the police that she had lost her work mobile phone in a mugging, but later discovered that it had not been taken.

She was released on parole in 2013, before becoming an MP.

Haigh’s is the first resignation from Sir Keir Starmer’s government and the 37-year-old said her appointment as the “youngest ever” female Cabinet member is “one of the proudest achievements of my life”.

However, he raises questions about the PM’s judgment in appointing someone with a conviction to his Cabinet, having previously attacked the Conservatives during the Partygate era, saying “people cannot the law to be a law maker”.

In 2013, Haigh was 24 years old and working as a public policy manager for the insurance company Aviva.

Following reports from Sky and The Times on Thursday, Haig issued a statement, explaining that she had made a police report following a “horrifying” mugging in London.

She said she reported the phone as one of several items she believed stolen, and was issued a new work phone.

Some time later, she discovered that the handset was still in her home, and switched it on, which “sparked the attention of the police” and she was called in for questioning.

“My solicitor advised me not to comment during that interview and I regret following that advice,” she said, and the matter was referred to magistrates.

Haigh said she had pleaded guilty to making a false police report at a magistrates’ court, six months before he became an MP in the 2015 election, and had been discharged – the “lowest possible outcome”.

She added: “On the advice of my solicitor I pleaded guilty – despite the fact that this was a serious mistake that I did not gain from.”

On Friday, she sent her resignation letter to Sir Keir Starmer, saying she did not want to be a distraction and that Labor would be “best served by my support from outside government”.

In response, Sir Keir said Haig had made “enormous progress” as transport secretary in returning the rail system to public ownership, and thanked her for her work.

Whitehall sources told the BBC that the transport secretary dshe announced when she was appointed to the shadow cabinet in 2020, when the Labor Party was in opposition.

Some are questioning why Sir Keir gave her the job when he was apparently told the details of this case when Haig joined his shadow cabinet.

Haig was responsible for one of the government’s main policies regarding the renationalisation of the country’s railway network under Great British Rail.

However, she became the first cabinet minister to publicly criticize the Prime Minister, over comments about P&O Ferries last month.

Haigh described P&O Ferries as a “rogue operator”last month and urged people to boycott the company, sparking a row with the ferry’s parent operation DP World.

When they threatened to boycott a major government investment summit in response, Sir Keir backed them up, saying Haig’s views were “not the government’s view”.

The mood in the Labor Party and in government has turned into a bit of a mess.

Almost everyone we spoke to this morning believed that the sequence of events described in Haig’s account was too small to warrant her departure, in the absence of further revelations.

But some believe she made the right political decision to act quickly rather than let the issue drag on for days.

One senior Labor figure described it to me as “a good resignation,” which could allow her to come back later with a clean slate.

Although Haig spoke in her letter of resignation from “our political project,” she and the prime minister were not always on the same page politically.

She was seen as one of the few remaining “soft left” ministers in her cabinet, who supported Jeremy Corbyn for the Labor leadership.

In the years before the election she was often accused – unfairly – of her job when the shadow cabinet was reshuffled.

A successor is likely to be announced today. The prime minister’s decision on who he calls up first from the bench to cabinet is being watched closely for guidance on who has influenced him during Labour’s short tenure so far. .

Born in 1987 in Sheffield, Haigh studied politics at Nottingham University and law at Birkbeck, University of London.

She worked as a shop steward for the Unite trade union and as a Metropolitan Police officer in the London borough of Lambeth before entering politics.

She has been MP for Sheffield Heeley since 2015 and held a number of shadow ministerial and shadow cabinet roles before becoming transport secretary when Labor won the election in July.

A Conservative Party spokesman said: “Louise Haigh has done the right thing in resigning. It is clear that she has failed to conduct herself to the standards expected of an MP”.