Senior Australian union officials face 15 years in jail over alleged blackmail

Two of Australia's most senior union officials will front court in Melbourne on Tuesday after being charged with blackmail.

The pair, Victorian secretary of the Construction, Forestry, Mining and Energy Union (CFMEU) John Setka and his deputy Shaun Reardon, face 15 years in jail if found guilty in the Melbourne Magistrates Court of the blackmail charges.

Setka and Reardon were arrested by Victorian police on Sunday for allegedly threatening concrete company Boral if it continued to supply concrete the CFMEU's main industry adversary, Grocon.

The CFMEU is Australia's main trade union in construction, forestry and furnishing products, mining and energy production.

Victorian Premier Daniel Andrews and Australia's federal Opposition leader Bill Shorten are under pressure to end the Labor Party's close relationship with the CFMEU after court judgments highlighted the union's disregard for the law.

The CFMEU has donated millions of dollars nationally to the Australian Labor Party in recent years, and 290,000 U.S. dollars to the Victorian branch of the Labor Party alone, between 2012 and 2014.

The charging of Setka and Reardon, two prominent members of Labor's Socialist Left faction, has sent shock waves through the Labor Party and the State government.

Andrews on Monday would not be drawn into commenting on the two arrests, saying he did not want to prejudice the men's trials.

"The problem with running an extensive commentary on these things is it's before the courts. Of course, you can, you can run your mouth off and talk about these things. Anyone who has done the wrong thing should feel the full force of the law, and if you get politicians pretending to be county court judges or magistrates, you can obviously compromise that," he told Melbourne radio on Monday.

"Journalists have got a job to do - they'll ask lots of questions - but I'm not going to be running a commentary on that, and to do so would be just wrong."

The charging of Setka and Reardon comes after an extensive investigation over the last year by a Victorian police taskforce codenamed Heracles. The taskforce was created to investigate information uncovered by the Royal Commission into trade union governance and corruption.

The commission found Setka threatened that if Boral did not stop supplying concrete to Grocon, the CFMEU would continue to escalate its black ban and ensure that Boral's overall market share was diminished.

The business damage is said to have been caused by a construction boycott of Boral in 2013, allegedly orchestrated by Setka and Reardon.

By making that demand, the commission found, Setka might have committed the criminal offense of blackmail, contrary to Section 87 of the Crimes Act. It said Reardon also might have committed the offense of blackmail.

CFMEU national secretary Dave Noonan slammed the police's handling of the arrests on Sunday, which he said were conducted in front of their respective families and "reek of overkill."

Noonan said treating union officials like fugitives was designed to create maximum political damage, with little regard for their families. Enditem