LEFT-wing supporters of Scottish Labour leader Richard Leonard want him to back sweeping changes to candidate selection procedures in a bid to get fresh blood into his MSP group.

Ideas being mulled over include giving trade union supporters a vote in internal regional List contests and allowing the leader to pick some of the candidates ahead of the next Holyrood election.

Mr Leonard became Scottish Labour leader last year after defeating centrist Anas Sarwar, but he has struggled to unite his divided group of MSPs.

Although he won the contest comfortably, a majority of MSPs voted for Mr Sarwar and Mr Leonard has faced various challenges to his authority.

He eventually sacked Mr Sarwar and senior MSP Jackie Baillie from his shadow cabinet this month amid claims they had undermined him.

Backers of Mr Leonard believe the MSP group will continue to be fractious unless a new crop of parliamentarians are elected in 2021.

Only three Labour members represent first-past-the-post constituencies at Holyrood, with the other MSPs being on the regional Lists.

In internal selections for Holyrood, Labour members are balloted and determine which candidates get a favourable slot on each List.

Although the membership is believed to be more left-wing than it was when the 2016 List ranking process took place, allies of Mr Leonard told this newspaper that they believe bolder reforms are required to guarantee personnel changes in the MSP group.

One possible change would be to widen the franchise for the List rankings so that trade union supporters could also vote in the internal ballot.

Around 10,500 supporters from affiliated trade unions signed up to vote in last year’s leadership contest, the overwhelming majority of which backed Mr Leonard.

It is believed that over 80% of the recruits were members of the Len McCluskey-led Unite union, which supports Mr Leonard and Jeremy Corbyn.

A second suggestion for reform is to dust down an idea floated when Kezia Dugdale led the party.

Under this plan, which was abandoned due to a lack of support, members would rank some of the candidates on each regional List, with the leader picking others.

One party source said: “Scottish Labour must field the best possible team as we approach the next election in 2021. The status quo, where sitting MSPs are virtually guaranteed a winnable list place based on name recognition alone, can’t continue.

“Richard Leonard must work with Labour affiliates to reach agreement on a formula which showcases the best talent in our Party and delivers a united and disciplined group. This will inevitably mean that some existing MSPs will have to make way for new faces.”

However, a source on the moderate wing of the party said: “The leadership contest descended into farce when trade union members who openly opposed Labour were given a vote. This idea is simply a tactic to ensure Len McCluskey can tighten his grip on Labour. Members will be absolutely furious if hard-working MSPs are deselected by people with no affiliation to the Labour Party and are replaced with Corbyn cultists.

“The purge of the moderates looks set to continue, which will move Scottish Labour even further away from power.”

Former MP Ian Davidson, who supports Mr Leonard, said Scottish Labour should not become as “sectarian as the Blairites” by embarking on a purge, but said: “The present group of Labour MSPs are unrepresentative of the Labour Party in Scotland and many have chosen not to adapt to the changed political climate.

"Many within it [the Group] have become too engrossed in internal rows and ignore why they were selected. They, or their candidates, have lost elections. They should get over it or get out. Some should change or be changed."

He added: "There needs to be a conscious effort made to widen further the pool from which candidates are drawn. Existing efforts should be continued, but even with present efforts there is too much replication of existing patterns. In particular, Labour has not managed to help sufficiently those with working class life experience and backgrounds."

In a statement released earlier this month after his recent shadow cabinet reshuffle, Mr Leonard said: "I have today asked [MP] Lesley Laird to carry out a review, reporting to me, of Scottish Labour’s organisation and operations to ensure that we are fully battle-ready for 2021. I want to thank our staff who work so hard and I know that the outcome of this review will help them and everyone in Scottish Labour deliver our shared objectives.

“I am also announcing that I will appoint a small working group in the coming week to ensure that we draw on a wider and more representative group of candidates for 2021, so that Scottish Labour is better connected to the communities we seek to represent.”

Scottish Labour did not provide a comment.