Senators Derryn Hinch and David Leyonhjelm in Twitter slanging match

The pair have clashed since it was revealed that Senator Leyonhjelm told a rally at Queensland Parliament in 2013 that he would be happy to let police "lie on the side of the road and bleed to death".

Complaining about new laws designed to deny affiliates of outlaw motorcycle gangs access to gun licences, the NSW senator said police and the public were on a collision course.

"For myself, I am never going to help someone who thinks it's OK to pull me up, search me and threaten me with jail if I don't answer their questions, merely because I ride my motorcycle in company with a couple of other people," he said at the protest.

"If that's what they think, they can lie on the side of the road and bleed to death."

After writing a blog post explaining his views and criticising Australians for being too quick to "excel at outrage", Senator Leyonhjelm turned his attention to Senator Hinch, who is a pro-police advocate.

"You need to read this and apologise to me, you dumb heap of parrot droppings," he tweeted, linking to the blog post and saying it was acceptable for Australians to criticise police.

Senator Hinch didn't pull any punches in his response, accusing his colleague of being a "a white-anting vandal".

Senator Leyonhjelm again pushed back.

"But you weren't defending police against vandals, you were mouthing off based on ignorance. Read my article, FFS," he said.

The senators will come face to face when Parliament resumes on November 7.

Earlier this month Senator Leyonhjelm defended attacking the late journalist Rebecca Wilson soon after her death from cancer.

Hours after Wilson's death was reported, he tweeted: "Doubt there'll be many #WSW [Western Sydney Wanderers] fans at Rebecca Wilson's funeral #innocentlivesdamaged."

The comment referred to Wilson's naming of Western Sydney Wanderers fans allegedly added to a list of banned soccer fans.