After the MP’s resignation, both major parties are weighing their options for a byelection in the seat of Perth

Tim Hammond’s resignation from federal parliament came not only as a shock, it has caught both major political parties on the hop, with the Liberals still considering whether they will even contest the seat of Perth.

Labor had not considered having to replace Hammond; the former lawyer was considered a surety for the seat for at least a decade.

The party is now scrambling to find a suitable candidate. The WA state Labor secretary, Patrick Gorman, a former staffer for Kevin Rudd, was one of the first hats thrown into the ring, but others were cautioning his candidacy was not set in stone.

Gorman was considered an early frontrunner, having led the party to its most decisive state win in decades, after Labor not only defeated the Barnett Liberal government, but did so in a majority.

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The Liberals were only in the early stages of their federal WA preselection motions, and the party is now preparing to talk to the Perth branch about whether that process should be expedited.

But despite winning just over 42% of the primary vote at the last general election, the Liberal candidate, Jeremy Quinn, still lost the seat because the Greens, who won 17% of the vote share, sent that vote to Labor.

Tim Hammond resigns, forcing Labor into Perth byelection Read more

To come anywhere near winning the seat, the Liberals would have to win more than 50% of the primary vote.

While Bill Shorten has visited the west 13 times since the last election, Malcolm Turnbull has been a much rarer sight, particularly since the Liberal state election loss and reignition of the GST debate.

With a general election due early next year, and Hasluck, Canning and Pearce to protect, a byelection is considered a costly distraction with no guarantee of success, particularly if the Greens run.

Which early inquiries suggested they would. They are in the final stages of their own preselections across the state, including for Perth.

Greens sources said Tim Clifford, who had previously contested the seat, was the most likely to win the preselection, but others questioned why he would leave his WA upper house spot for an unwinnable seat. Other political insiders wondered whether Scott Ludlam, who left the Senate as the first section 44 casualty, would seek to return.

Other Greens members said preselection processes had finished, but would not say who the winning candidate was.

There is thinking within the Liberal party to let Labor and the Greens spend their resources battling it out, as they did in Batman, the seat of Perth having been in Labor’s hands since 1983.

A boundary change shortly before the 2016 election shifted the electorate into slightly more marginal territory for Labor than it had been before.

Hammond won the seat after Alannah MacTiernan stepped down after one term, with a 3.3% margin. MacTiernan returned to state politics.

Others are also questioning whether the Perth byelection will be held in isolation, with the high court ruling on Katy Gallagher’s eligibility to sit in the Senate having the potential to set off a domino effect for Labor MPs Susan Lamb, Justine Keay and Josh Wilson.

That would see Labor fighting two byelections in Western Australia, as well as one in Queensland and one in Tasmania, as well as South Australia if the Centre Alliance MP Rebekha Sharkie is also made to resign under the Gallagher ruling.

With discussions over preselections only just starting, Labor has not begun to consider who will take Hammond’s place on the frontbench, although Terri Butler and Kristina Keneally were both touted as early contenders.

Hammond resigned on Wednesday, announcing his decision on Perth radio after admitting he could no longer balance his work and family life.

“I don’t want to dig into the really personal particulars of how that has unfolded, particularly in the last six to two months, other than to say we have tried everything we can to keep all of this together in a way that isn’t going to compromise the strength of what we all have as a family,” he told 6PR in an emotional interview.

“I just can’t risk the consequences of delaying this for another almost 12 months, even if it means going to the backbench, even if it means really scaling back my role, and all of those things have been offered.”

Hammond has not yet formally resigned, meaning no writs for a byelection can be issued.

That is expected to happen some time in the next parliamentary sitting week, when the government will also hand down its pre-election budget.