Speaking in the chamber on Wednesday,Senator Patrick revealed that Mr Setka's expletive-ridden tirade against him and Tasmanian senator Jacqui Lambie had been referred to the Australian Federal Police,"who are now looking into the matter".
It is understood that Labor will back Senator Patrick's motion,meaning it will pass easily with the government set to back the push.
Mr Setka,the CFMMEU's Victorian construction secretary,told a union meeting last weekthat "f---ing crossbenchers" would "wear the consequences" if they voted in favour of the union-busting Ensuring Integrity Bill.
In a radio interview on Wednesday,he rejected Senator Patrick and Senator Lambie's allegation the comments amounted to"threats"aimed at influencing their votes,telling ABC Radio National he had only been "campaigning against draconian laws that people are considering passing".
Mr Setka also defended his comments,recorded at a meeting of about 300 shop stewards last week,that played down his June conviction for harassing his wife and breaching court orders,dismissing his criminal behaviour as a"few bad text messages"between a husband and his wife and saying,"Big deal".
He said no"threat"had been made against the senators,who should"toughen up".
"When you're a politician,you've got to get used to campaigning. It's a two-way street;they have their say,I have my say,"he said.