The unapologetic world of Australia's 'nastiest' politician

David Leyonhjelm was once branded the "nastiest, most sexist politician in Australia".

He's labelled a fellow Australian MP a "dumb heap of parrot droppings", has put forward a law inspired by notorious criminal Mark "Chopper" Read and unleashed profanities to silence his critics on Twitter.

David Leyonhjelm, a cat-loving former veterinarian and Liberal Democratic senator for New South Wales, has twice been elected to federal parliament, and is one of a disparate group of cross-benchers who hold the balance of power in an unpredictable upper house.

He is his libertarian party's sole representative in Canberra, and has been branded "the nastiest, most sexist politician in Australia" by Sydney Morning Herald columnist Peter FitzSimons.

FitzSimons, a former rugby union international, told his readers a story about an elderly female reader who had taken exception to the senator's relaxed view on Donald Trump's crass remarks about women.

She complained and received a brusque response saying she was "not fit to use a computer".

"Apparently a constituent wrote to me and made some fairly silly remarks. I have a fairly low tolerance for idiots," Senator Leyonhjelm told the BBC from his offices in Sydney.

"It was fairly idiotic email, so I wrote back to her and called her a bimbo. I had no idea [but] it turns out she is in her 70s or 80s or something like that and she complained to this sports writer."

Leyonhjelm referenced criminal Mark 'Chopper' Read in a debate over a discrimination law

"He contacted my office and asked for a comment and one of my staff replied we had no comment for him about the particular matter but… said 'well, usually he [the Senator] tells people like that to [profanity]-off, and he didn't in this case, so we're worried that he is mellowing.

"Apparently that enraged this guy."

It sure did. A fired-up FitzSimons added that "with such personal abuse, the Senator disgraces the office he holds".

This is not the first time the Liberal Democratic MP has been castigated in the press. In August, the Herald labelled him a "hate-speech apologist" and "a boorish, supercilious know-all with the empathy of a [concrete] besser block".

At issue is the senator's push to repeal section 18C of Australia's Racial Discrimination Act, which outlaws behaviour that is likely to "offend, insult, humiliate or intimidate" someone because of their race or ethnicity. Here is where he channels memories of "Chopper" Read, who died in 2013 after serving 23 years in jail in Australia for kidnapping and malicious wounding.

"Our right to free speech is not a frivolous matter, but it is time for sooks and whingers to take a leaf from Chopper. It's not the government's job to protect us from hurt feelings," Senator Leyonhjelm said on his official website.

Feelings were certainly singed following a tweet soon after the death from cancer of the celebrated sports journalist Rebecca Wilson.

"Doubt there'll be many #WSW [Western Sydney Wanderers] fans at Rebecca Wilson's funeral #innocentlivesdamaged," he tweeted in reference to the late reporter's identification of fans allegedly on a banned list for poor behaviour, most of whom were followers of Western Sydney Wanderers.

'Extreme tactics'

"He takes bluntness to a higher level. He can be obscene at times but it is in Australia's more rough and tumble tradition," explained Dr Peter Chen, senior lecturer in the department of government and international relations at the University of Sydney.

"He originally was a member of the Labor Party. He joined the Liberal Party and he fell out with both sides of politics, most recently with his membership of the Liberal Party over the introduction of gun laws in Australia following the Port Arthur shooting about 20 years ago," Dr Chen added.

Senator Leyonhjelm is broadly in favour of immigration, supports same-sex marriage, lower taxes and assisted suicide, but it's restrictions on firearms that make his blood boil.

Senator Leyonhjelm has been very critical of Australia's tough gun laws

"I find that distressing because it is wrong and it is very unkind to me and 800,000 licensed shooters in the country, who are absolutely vilified, treated like we are criminals-in-waiting and whose sporting implements are constantly under threat," he explained.

His critics argue that his stance on guns ignores the opinions of most Australians, who back tough laws.

"He is using extreme tactics to push through his quite dangerous agenda," said fellow New South Wales Senator Lee Rhiannon, from the Greens, who is her party's gun control spokesperson. "He has been provocative, blunt, extreme, at times rude."

She concedes, however, that Senator Leyonhjelm and Pauline Hanson's right-wing anti-immigration One Nation Party are tapping into anti-establishment rage in Australia.

"We're seeing a real anger build up within the community with regard to machine politics, the political class, whatever name you want to call it, who are worried how their kids are going to buy a home and feeling left out of how society is working," Ms Rhiannon told the BBC.

"They think that globalisation has robbed them of a life that they think is fair."

The Liberal Democrats say they have recruited hundreds of disaffected former supporters of the governing Liberal Party and hope to mount a show of force at the next year's state election in Western Australia.

That campaign promises to be anything but dull. Lampooned by TV comedians in June, Senator Leyonhjelm reacted in trademark fashion by swearing at the crew and telling them to leave.