Night at the Iguanas could finally end the career of 'Toxic Belinda'

It started as an argument between a husband and wife political team and staff at Iguanas Waterfront Bar, a restaurant north of Sydney. Now it's Iguanagate – a scandal that could claim the scalp of one of Prime Minister Kevin Rudd's new intake of Labor MPs.

Staff claim Belinda Neal, 45, abused and threatened them when they asked her party of nine to move tables, so they could transform part of the venue into a nightclub. She allegedly asked them: "Don't you know who I am?", demanded one employee be sacked, and told the operations manager: "I will have your fucking licence. You will not be trading in three months' time."

Ms Neal's husband, John Della Bosca, the education minister in the New South Wales state government, has already lost his job over the matter. Now attention is turning to one of the stars of Mr Rudd's government. While Ms Neal, who has been dubbed "Toxic Belinda", has denied any wrongdoing, Mr Rudd interrupted a state visit to Japan to order her to undergo anger management counselling. This week, after she refused to be interviewed by police, he reminded her – for the second time in a month – that "no one is guaranteed of a future in politics".

Managers at Iguanas were so alarmed about the incident that they asked six staff members to sign statutory declarations about the evening's events. Police are investigating discrepancies between the statutory declarations and statements by four members of Ms Neal's party, defending the couple's behaviour. One of the four, an aide to Ms Neal, has resigned, claiming the MP forced her to remove damning sections from her statement.

Ms Neal, whose long-held ambition to become an MP was fulfilled last November when Mr Rudd came to power, finally agreed to be questioned by police on Thursday. Yesterday it was reported that Labor power-brokers had ruled out preselecting her at the next election – a claim that was officially denied. But she could be expelled or suspended from the party if the police inquiry leads to charges such as conspiring to pervert the course of justice.

Since the Night of the Iguana, further stories about Ms Neal have come thick and fast. She was suspended from a women's football competition after a dangerous tackle on a young opponent, whom she denied kicking on the ground. She told a pregnant opposition MP during a parliamentary debate that "evil thoughts will turn your child into a demon". She was fined for keeping a dangerous dog, a kelpie called Checkers, that attacked a cyclist. She is said to keep the names of her enemies – and there are many – in the freezer.

One political journalist, Malcolm Farr, of the Sydney newspaper The Daily Telegraph, related an episode at a Labor conference in 2002. "A TV cameraman ... stopped in front of Belinda Neal, who was filing her nails," he said. "She looked up, scowled and extended a recently manicured middle finger to the cameraman, and later to several thousand viewers."

Most damagingly, claims have been widely aired that Ms Neal – who is said to have prime ministerial aspirations – physically abuses her husband. Neighbours say police have been called to their home several times. But some female MPs have defended her, saying she would not be subjected to such criticism if she was a man.