With a new leader and tired opponent, this should be the Victorian Liberals’ year – if not for self-inflicted wounds | Victorian politics

This should be the Victorian Liberal party’s year. They head into November’s election with a new, energetic and articulate leader in Jess Wilson, who has vowed to drag her party to the centre and reconnect with voters it has lost in recent years.

Across the aisle stands a weary third-term Labor government, burdened by the state’s debt – forecast to hit $192bn by 2028-29 – and the baggage of more than a decade in power. No Victorian Labor government has ever secured a fourth term – a fact that should give the Liberals cause for optimism.

But the past week has shown, once again, the party’s greatest obstacle to winning government is not Labor – but itself.

The week began with a statement on Monday morning, in which the party’s star recruit Sam Groth announced he would quit politics at the November election due to infighting.

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For Wilson – herself just 35 – Groth standing beside her would have been an asset in the lead-up to the poll: a visible symbol of a refreshed, modern Liberal party. The only upside of Groth’s departure is it removes a potential future rival.

The former professional tennis player joined the party during the pandemic and, after receiving special dispensation to run, won back the seat of Nepean from Labor at the 2022 election.

But Groth’s outsider status, combined with his rapid rise from first-term MP to deputy leader, also made him unpopular within the Liberal party room, particularly among colleagues who felt he hadn’t paid his dues and privately described him as not up to the job.

That hostility manifested in backgrounding and backstabbing, which ultimately ended up crossing a line when the Herald Sun published a series of articles alleging Groth and his wife, Brittany, may have begun their relationship when she was underage and under his supervision as a tennis coach.

Groth sued for defamation and Brittany launched the first test of a new statutory tort for serious invasions of privacy. While the matter was ultimately settled out of court and the Herald Sun apologised to the couple, its defence revealed an unnamed Liberal MP had been central to the story.

Groth’s resignation statement alluded to this betrayal: “The public pressure placed on my family in recent months has been significant and realising that some of it came from within my own party has been difficult to ignore.”

For Wilson, who has cast herself as the leader of a unified team, the episode is damaging.

And her challenges won’t end there. Guardian Australia this week revealed Moira Deeming and Ann-Marie Hermans will face preselection challenges in March, with a prospective candidate also being urged to run against Renee Heath.

Sources suggest while Heath could survive, Herman’s political career is less certain. And if Deeming’s challenger, Dinesh Gourisetty, commands the numbers his supporters claim – along with backing of the party’s administrative wing – she too is in trouble.

It would be naive, though, to think Deeming would go quietly. The MP became a darling of conservative media after she successfully took the former leader John Pesutto to court for defamation – with the judgment kiboshing his leadership.

She was urged again and again not to go ahead with the defamation action, to settle and then to offer Pesutto a deal on the $2.3m bill in legal costs he owed her. Deeming didn’t back down.

Unlike Labor, where most political manoeuvring occurs by its factions behind closed doors, Liberals pride themselves on a rank-and-file-driven preselection process, making it difficult for Wilson to intervene. It’s understood she has written endorsements for any MP who has asked for one, including Heath and Deeming.

There are said to be more preselection challenges afoot. Expect damaging headlines between 14 January, when nominations close, and voting in late March.

Hovering over all of this is a supreme court trial, set to begin in March, challenging the legality of the $1.5m loan the party executive extended to Pesutto to pay Deeming’s legal fees. In a further sign of the party’s dysfunction, the case is being pursued by a group of the executive’s own members.

This is not something Wilson will be able to dismiss as “historical”, as she attempted to do with Groth’s resignation.

It’s clear the party – and Wilson – knows that it needs to stick firmly in the middle to win the election. But can it withstand the likely self-inflicted damage it will take to get there?

Benita Kolovos is Guardian Australia’s Victorian state correspondent