Mike Amesbury has announced he will stand down as an MP after he was convicted of punching a man in the street.
A by-election will now be triggered in his seat of Runcorn and Helsby, where constituents will vote to elect a new MP.
Amesbury, who was suspended from the Labour Party, was jailed on 24 February for 10 weeks after he pleaded guilty in January to assault by beating of 45-year-old Paul Fellows in Main Street, Frodsham, Cheshire, in the early hours of 26 October.
However, following an appeal, his sentence was suspended for two years, so he does not have to serve it in prison.
Amesbury, 55, told the BBC on Monday he will begin the “statutory process” of closing up his office before resigning as an MP “as soon as possible”.
His resignation will trigger a by-election – the first of Sir Keir Starmer’s Labour government.
He said he regrets the attack “every moment, every day” and said he would have tried to remain as an MP if he had been given a lighter community sentence.
Parliamentary rules state any prison sentence, even suspended, given to an MP triggers a recall petition.
A by-election will then be called if 10% of constituents vote to remove him as their MP.
Amesbury has continued to take his £91,000 salary after he was sentenced, including when he spent three nights in prison before his appeal was successful.
He told the BBC he carried out casework while behind bars as his office manager forwarded on emails.
“Life doesn’t stop as an MP,” he said.
Labour suspended Mr Amesbury from the party shortly after the incident, so he has been sitting as an independent MP in the Commons.
The party said he would not be readmitted to Labour and had called for a by-election, saying Mr Amesbury’s constituents “deserved better” after his “completely unacceptable actions”.
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