A bid to overturn the endorsement of three federal Liberal MPs as candidates in the looming election has been dismissed by a NSW court, in a major win for Prime Minister Scott Morrison.

The NSW Court of Appeal on Tuesday rejected a legal challenge launched by Sydney businessman and NSW party executive Matthew Camenzuli, who sought to have the “purported” preselection of the MPs declared invalid.

If he succeeded, Mr Morrison faced the prospect of losing ministers Sussan Ley and Alex Hawke and backbencher Trent Zimmerman.

The trio were preselected in March after the federal party intervened, temporarily took over the NSW branch, and appointed a panel to finalise the last batch of NSW candidates ahead of the election, due in May.

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That panel – consisting of Mr Morrison, NSW Premier Dominic Perrottet and former federal party president Chris McDiven – has since approved nine more candidates.

Mr Camenzuli’s barrister Scott Robertson had argued that the panel had no power to overrule the right of rank-and-file members – enshrined in the Liberal Party’s constitution – to preselect their candidates.

But on Tuesday, three judges ruled that the dispute over preselection processes was not something the court had the jurisdiction to intervene in.

“The nomination and endorsement provisions do not confer statutory rights upon candidates at the anterior stage of preselection,” Justice John Basten said.

“The dispute is not justiciable.”

Even if the court did have jurisdiction, the selection panel did not exceed the “broad power of intervention” conferred to it under the party’s federal constitution, and the challenge would have been rejected.

The decision comes after months of factional infighting, and could pave the way for similar interventions by the federal party executive in the future.

It is also the final hurdle Mr Morrison needed to clear before calling the election. However, it did not signal an end to his troubles within the NSW Liberal Party.

Another Liberal MP called out his character on Tuesday, saying she could not vote for a “a ruthless self-serving bully” and no longer recognised the party she joined.

NSW state Liberal MP Catherine Cusack attacked Scott Morrison’s handling of the recent floods, accusing him of politicising the tragedy.

“I can’t vote for Scott Morrison, full stop, at the next federal election,” she told the ABC.

“Doing the right thing now won’t get my vote because it won’t undo the wrong he has done to my community.”

Elsewhere, the Sydney Morning Herald was reporting on Tuesday afternoon that members of one Sydney Liberal branch have withdrawn their support for sitting MP Fiona Martin.

The heads of the Liberal Party’s Strathfield women’s branch said their friendship with high-profile former Liberal Party member Natalie Baini – who will stand against Dr Martin as an independent – was a conflict of interest and they would support candidates in Lindsay and Fowler instead.

Strathfield women’s branch president Liana Ross and secretary Vivian Hodgson also cited personal issues with one of Dr Martin’s campaign managers.

Dr Martin, a child psychologist, was described as a captain’s pick when she was selected to run for the inner-Sydney seat of Reid in 2019.

Earlier, Ms Cusack accused Mr Morrison of using his role as prime minister to bully NSW government and flood victims because he is not getting his way.

This was evident in the political appointment of Shane Stone as the co-ordinator-general of the National Recovery and Resilience Agency and using guidelines to exclude some flood victims, she said.

Ms Cusack, a member of the NSW upper house who lives in the flood-hit NSW northern rivers, also accused Mr Morrison of failing to engage with the state government on assessing and approving payments and co-funding a recent disaster package.

“As a result, those packages are well below what’s required and what should be available,” she said.

“It is unbelievable anyone would act like this towards flood victims.”

Mr Morrison said in Sydney the federal government had invested $2.1 billion on the NSW flood response.

He said some programs would be fully funded by the state and some would have their costs shared with the Commonwealth.

Assistant minister Tim Wilson defended Mr Morrison, saying there would always be “people who will be upset or disgruntled about previous experiences”.

“I’ve always found my engagements with him (Mr Morrison) to be incredibly professional and engaged in good faith,” he said.

A new poll on Tuesday put Labor 14 points ahead of the Coalition, following criticism from ousted NSW Liberal senator Concetta Fierravanti-Wells about Mr Morrison’s character and trustworthiness.

A Roy Morgan poll conducted in the past week showed the ALP extending its lead to 57-43 in two-party preferred terms – a 1.5 percentage point increase from a week prior.

Senior Labor figures are trying to play down their lead in the polls, with frontbencher Chris Bowen saying the party needs to “win seats, not polls”.

Labor leader Anthony Albanese admitted his party had a mountain to climb, having won from opposition only three times since World War II.

“I’m only worried about a poll on polling day,” he said.

“We are putting forward a constructive plan for the nation’s future – one where no one is held back and no one is left behind.”

Mr Morrison sought to turn attention to the relief the government’s 22-cents a litre cut to the fuel excise was providing.

“We are seeing … [price] falls already – all around the country,” he said.

Shadow treasurer Jim Chalmers used a National Press Club address to attack stagnant wages growth under the Coalition.

“If last week had been a Labor budget … it would have invested in productivity, so we can grow the economy more strongly without runaway inflation,” he said.

-with AAP

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