Transport Secretary Louise Haigh has admitted pleading guilty to an offence connected with misleading the police while a parliamentary candidate in 2014, Sky News can reveal.

Sky News understands Ms Haigh appeared at Camberwell Green Magistrates’ Court six months before the 2015 general election, after making a false report to officers that her mobile phone had been stolen.

Ms Haigh said she was “mugged while on a night out” in 2013. She then reported the incident to the police and gave officers a list of items she believed had been taken – including a work mobile phone.

In a statement to Sky News, the transport secretary said she discovered “some time later” that “the mobile in question had not been taken”.

She added: “In the interim, I had been issued with another work phone.”

The transport secretary said: “The original work device being switched on triggered police attention and I was asked to come in for questioning.

“My solicitor advised me not to comment during that interview and I regret following that advice.

“The police referred the matter to the CPS and I appeared before Southwark magistrates.”

Ms Haigh continued: “Under the advice of my solicitor I pleaded guilty – despite the fact this was a genuine mistake from which I did not make any gain.

“The magistrates accepted all of these arguments and gave me the lowest possible outcome (a discharge) available.”

It’s understood her conviction is now classified as ‘spent’.

However, three separate sources claimed she made the false report to benefit personally, with two of the sources alleging she wanted a more modern work handset that was being rolled out to her colleagues at the time.

The now cabinet minister had been working as a public policy manager at Aviva, but two sources said she lost her job at the insurance firm because of the incident.

Her government profile states she left this role in 2015 before becoming the MP for Sheffield Heeley at that year’s general election.

Sky News understands the incident was disclosed in full when Ms Haigh was appointed to the shadow cabinet.

In the statement given to Sky News, the transport secretary said: “I was a young woman and the experience was terrifying.”

Conservative Party Chairman Nigel Huddleston told Sky News the revelations are “extremely concerning”.

He added: “Keir Starmer has serious questions to answer regarding what he knew and when about the person he appointed as transport secretary admitting to having misled the police.”

Before entering politics, the transport secretary was a special constable in the Metropolitan Police – serving between 2009 and 2011 in the South London Borough of Lambeth, close to where she was convicted several years later.

She was appointed shadow policing minister by Jeremy Corbyn in 2017 and frequently drew on her experience in the Met when challenging the Tory government on the rising demands on officers.

As transport secretary, Ms Haigh appoints members of the board that oversees the British Transport Police.

In 2019 she said that Boris Johnson had “deceived the police” and committed a “serious breach of trust” over claims he politicised serving officers during a speech in West Yorkshire.

Sir Keir Starmer promoted the Sheffield MP to shadow Northern Ireland secretary in 2020 before moving her to shadow transport secretary in 2021.

In this brief she has been an outspoken critic of the mass sacking of 800 workers by P&O Ferries in 2022.

In October, while transport secretary, she accused P&O of being a “rogue operator” and called for a boycott of its services.

The comments caused the firm’s Dubai-based owner to review a planned £1bn UK port investment – something that was re-confirmed after ministers held urgent talks with the company.

But she was publicly rebuked by Sir Keir who said her opinions were “not the view of the government”.

With connections to former Downing Street chief of staff Sue Gray, there has been speculation her cabinet role could be under threat in a future reshuffle.

Ms Gray’s son, Labour MP Liam Conlon, is Ms Haigh’s parliamentary private secretary and acts as her “eyes and ears” in parliament, while another of her former employees also worked for the former chief of staff before she was sacked after losing a power struggle within Number 10.

As transport secretary, Ms Haigh was one of a handful of cabinet ministers who complained to the Treasury about impending cuts in the budget.

She is considered to be one of the more left-wing members of the cabinet and has vowed to “rip up the roots of Thatcherism” with her plans for rail and bus reform.

In 2015, Ms Haigh was one of a number of Labour MPs to nominate Mr Corbyn for leader – a decision she later said she regretted.