Anyone with information on corrupt union practices should go to the police, acting Opposition Leader Tanya Plibersek says.

Ms Plibersek was responding to calls by Attorney-General George Brandis to reinstate the Australian Building and Construction Commission (ABCC), after a joint ABC-Fairfax Media investigation claimed union officials were making corrupt deals to help companies linked to organised crime secure construction contracts.

When asked by reporters whether the ABCC needed to be resurrected, Ms Plibersek said current laws already covered the sector.

“Anybody that has information that would suggest any inappropriate behaviour on the part of a union official should report that to the police or other appropriate authorities,” Ms Plibersek told reporters in Sydney on Tuesday.

She said the previous Labor government had introduced laws governing union transparency.

The government says the media report highlights the pressing need for the industry watchdog the ABCC to be re-established.

The commission was replaced with a Fair Work inspectorate by the previous Labor government, and Labor and the Greens are now blocking legislation for a new ABCC in the Senate.

On Tuesday it was revealed a lucrative contract at James Packer’s $6 billion casino project had been granted to a labour hire company run by George Alex, who has known links to criminal and bikies gangs, after intervention from allegedly corrupt Construction, Forestry, Mining and Energy Union (CFMEU) officials.

NSW Premier Barry O’Farrell on Tuesday said an investigation into allegations of corruption at the Barangaroo South construction site was warranted.

“Matters like this are of serious concern, not just to the state government but also to the construction sector,” Mr O’Farrell said.

But, he added, it was important to remember that only about 50 of the 600 workers at the site were caught up in the allegations.