Changes to the way the Labour Party elects its leader will make it much harder to mount a coup and effectively guarantees a leader's job is safe in between elections barring a major caucus revolt.
Labour announced the changes yesterday, including giving about 45,000 party members and union affiliate members a vote on the leadership which is currently voted on by MPs only.
Under the new voting system the votes of members and caucus will count for 40 per cent of the vote each and the affiliated unions' vote will count for 20 per cent.
However, only caucus will be able to force a leadership vote and then only in restricted circumstances.
There will be a regular confidence vote within three months after an election but other than that, the only other way the leader can be changed is if two-thirds of caucus sign a petition - a much higher threshold than the simple majority required to roll leaders under the current system.