New Labour members will be required to sign a pledge promising not to abuse anyone online or face being kicked out of the party.
The tougher stance on internet behaviour was agreed by Labour’s National Executive Committee (NEC) after centrist MPs protested about a torrent of abuse from supporters of Jeremy Corbyn.
It came as one of those MPs - Stoke-on-Trent’s Ruth Smeeth - revealed she will be taking a "minder" to the party’s annual conference in Liverpool, starting this weekend.
“I will have someone with me. I haven’t felt the need to do this before, but it is a sensible security precaution for obvious reasons at the moment”, Ms Smeeth, who is Jewish, told The Sun.
“But I’ve been to conference every year since 1999 and I’m not going to stop going now.”
The MP has been taking advice from the police about security after receiving death threats online and a total of 25,000 abusive messages, many of them anti-Semitic attacks.
The NEC, which deferred a decision on a return to Shadow Cabinet elections, unanimously agreed the beefed-up code of conduct on social media behaviour, to be included in the terms and conditions of membership.
Party members will have to promise explicitly “to act within the spirit and rules of the Labour party in my conduct both on and offline, with members and non-members”.
The statement adds: “I stand against all forms of abuse. I understand that, if found to be in breach of the Labour Party policy on online and offline abuse, I will be subject to the rules and procedures of the Labour Party.”
Punishment could include being suspended from the party or eventually expelled.
The signed pledge will be linked to an existing social media code of conduct, drawn up by the party, which warns that "harassment, intimidation, hateful language and bullying" will not be tolerated.
It also lists discrimination on the basis of gender, race, religion, age, sexual orientation, gender identity or disability.
The code reads: “Abusing someone online is just as serious as doing so face to face. We stand against all forms of abuse and will take action against those who commit it.
Ms Smeeth said she has been called a "CIA/MI5/Mossad informant", and a "f***ing traitor". She maintained abuse had become normal for many of her colleagues.
She hailed the pledge as “a great step forward”, adding: “MPs have been subject to a tsunami of abuse. It is unfortunate that we've got to this place but, given the changing nature of social media, I welcome the proposal.”
Some MPs have criticised Mr Corbyn for not taking strong enough action to protect Labour politicians from abuse from his own supporters.
But the party leader backed the tougher stance and has said he has also suffered abuse – which must never be tolerated.
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