The Greens’ shock loss in Saturday’s Batman by-election has left the party divided and reeling, with federal leader Richard Di Natale promising to hunt down and expel party members who “sabotaged” the election campaign.

On Saturday night Labor candidate Ged Kearney won the seat with 54.6 percent of the two-candidate-preferred vote, representing a 3.6 percent swing towards Labor. The Greens, who went into the by-election as favourites, are now facing serious questions about their political strategy and fingers are already being pointed at internal dissidents who orchestrated a series of leaks designed to undermine the party’s candidate, Alex Bhathal.

Batman wasn’t the only bad news for the Greens over the past weekend. The party lost a quarter of its vote at the SA state election, also held on Saturday, polling just 6.6 percent. Just a few weeks ago the party suffered a poor result in Tasmanian state election, polling one of its lowest votes on record.

The party has been beset by significant factional issues recently, and the Batman by-election result shows that unless the party grapples with its internal tensions it’s vote is likely to remain stagnant.

What Happened In Batman?

At the 2016 federal election the Greens came within one percent of winning Batman from incumbent Labor MP David Feeney, who eventually resigned over citizenship issues, triggering Saturday’s by-election.

Feeney, a factional powerbroker from Labor’s right-wing, was always an odd fit in the left-leaning seat of Batman. The Greens have been closing the gap against Labor since Feeney was first elected in 2013. In 2016 he was able to scrape over the line with the aid of Liberal preferences, and the Liberal party’s decision to not run a candidate in the by-election was widely seen as a move that would benefit the Greens.

But Kearney, a high-profile trade unionist, appears to have undone the damage Feeney inflicted on Labor’s brand in the seat. Labor made significant inroads in the southern half of the electorate, which has historically been the Greens’ strongest area. Kearney was a strong candidate and Labor’s campaign was expertly run with a heavy focus on bread and butter issues like education and transport.

The Greens’ campaign, on the other hand, was repeatedly rocked by damaging leaks targeting Bhathal. It became apparent during the election campaign that a number of members would rather the party lose the seat than win with Bhathal as candidate.

Why Did Some Greens Want Bhathal To Lose?

Often, the most bitter political fights happen within parties rather than between them. While some internal tensions are caused by ideological disagreements, it appears the leaks against Bhathal were driven more by personality issues.

Greens sources have told Junkee they believe a group of members aligned to the party’s Darebin councillors were part of the orchestrated campaign against Bhathal as revenge for Bhathal backing Lidia Thorpe in a preselection battle for the seat for Northcote against Darebin councillor Trent McCarthy. Thorpe went on to win Northcote, becoming the first Aboriginal woman elected to the Victorian state parliament.

All political parties have internal tensions, but it’s rare for members to actively try sabotage their own candidate’s campaign in this way.

Throughout the campaign Di Natale expressed frustration at the leaks. In an interview with the ABC’s Patricia Karvelas on Sunday night, he said: “We had a very strong candidate but the bottom line was we had a very small group who… felt that they wanted to undermine her chances and the Greens chances of taking that seat”.

“In the end we weren’t just fighting our ALP opponents we were fighting a small group of our own people… that set us an impossible task,” he said.

Di Natale announced that the party would launch an investigation into the leaks and expel anyone found responsible. The co-convenors of the Victorian branch of the party wrote to members on Sunday promising to investigate “the sabotage” and take “swift action”.

What Does This Mean For Richard Di Natale’s Leadership?

Unsurprisingly the string of poor results for the Greens lately has raised speculation about Di Natale’s leadership of the Greens. A former convenor of the NSW Greens, Hall Greenland, circulated a message to members on the weekend suggesting the result demonstrated the Greens needed to shift further to the left.

Di Natale has a number of detractors in the NSW branch of the party and they’re seizing on the Batman result as evidence that his leadership is stalling the Greens vote. In 2016 he announced he wanted the party to win eight lower house seats by 2026, but the failure to secure Batman puts a significant dent in those plans. It’s unlikely the Greens will get another opportunity in the near future to pour significant resources into a progressive seat with no incumbent Labor MP and without a Liberal candidate directing preferences to Labor.

Interestingly, Di Natale pointed to recent Greens successes at the Queensland state election last year when asked about the impact of his leadership on the party’s election result. The party won it’s first seat in Queensland parliament and received a huge 12 percent swing in the targeted seat of South Brisbane, coming within 4 percent of victory.

But the Queensland Greens don’t ascribe this success to Di Natale. In fact, they suggest the opposite. Queensland Greens sources told Junkee they did their best to keep Di Natale away from their campaign and that their messaging ignored what was coming out of the federal party room. Other Queensland Greens figures have publicly distanced themselves from the federal party room.

Despite the public soul searching, it’s extremely unlikely Di Natale will either step down or be forced out of the leadership. The Greens party room is a small and intimate forum, and the party has no history of the leadership switches that have plagued the major parties. That doesn’t mean there won’t be a real debate about the party’s future strategic direction, though it’s likely to come from the grassroots rather than be driven from the top.

Di Natale’s focus on expelling leakers is about both reclaiming authority and attempting to ensure the public debate is about the party’s “culture” rather than it’s ideology. But the shock result on Saturday makes it unlikely the party leadership can keep a lid on the long-simmering internal tension across the party for much longer.