Mr Pincher, who has been the MP for Tamworth since 2010, resigned from his job as deputy chief whip in July last year following allegations about his conduct.

Mr Pincher was accused of groping two men in a private members club and apologised for "drinking far too much" and embarrassing "himself and other people".

Mr Johnson then suspended Mr Pincher from the Tory party after he came under pressure to take swift action in the wake of the allegations.

It later emerged that Mr Johnson had already been told about an investigation into Mr Pincher's conduct three years earlier, but in a subsequent apology, he suggested he forgot he was informed.

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In an explosive letter to parliament's standard's commissioner, former Foreign Office permanent secretary Lord McDonald accused Downing Street of making "inaccurate claims", saying they "keep changing their story and are still not telling the truth".

Downing Street eventually admitted that Mr Johnson had been told about an investigation into Mr Pincher's inappropriate behaviour in 2019, despite days of saying he had been unaware of specific allegations against his former deputy chief whip.

Although Mr Johnson apologised, the former prime minister's handling of the scandal precipitated his downfall, having followed months of allegations of rule breaking in Downing Street during the COVID pandemic.

A number of Conservative MPs criticised Mr Johnson over the Pincher affair, with former chief whip and current transport secretary Mark Harper telling Sky News at the time that senior cabinet ministers should consider their positions.

His remarks echoed the sentiment of committee chair William Wragg, who accused the government of having "no regard" for upholding standards in public life.

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MPs' goodwill was also tested by the government's attempts to change the rules to prevent the suspension of then Conservative MP Owen Paterson after he broke lobbying rules.

Moments after Mr Johnson apologised for appointing Mr Pincher, Rishi Sunak and Sajid Javid resigned from their cabinet positions as chancellor and health secretary, respectively.

It sparked a wave of resignations that led to the collapse of Mr Johnson's government.

Mr Pincher has represented his constituency in the Commons as an independent MP ever since he was stripped of the Tory party whip.

He remains under investigation by the parliamentary commissioner for standards for "actions causing significant damage to the reputation of the House as a whole, or of its members generally".

Mr Pincher is one of a number of MPs to have announced they are standing down at the next election.

Mr Javid, former health secretary Matt Hancock and Tory MP Nadine Dorries are among the prominent names who will not seek a return to the Commons.