Labor has slammed Malcolm Turnbull for living the "high life" while using thinly-stretched federal police resources to target trade unions at the expense of crime.
Australian Federal Police officers on Tuesday raided the Sydney and Melbourne offices of the Australian Workers Union at the behest of the Registered Organisations Commission, which is investigating the legitimacy of a $100,000 donation to activist group GetUp! in 2005.
"Malcolm Turnbull is living the high life in his harbourside mansion surrounded by federal police," Labor senator Doug Cameron told reporters in Canberra on Wednesday.
"In the same week the federal police is saying it doesn't have enough resources to deal with drug smuggling, illegal arms and terrorism in this country."
Senator Cameron said there were checks and balances in trade union rules to prevent the misuse of funds and that the AFP raids were "absolute overkill".
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Cabinet minister Simon Birmingham insisted the commission's investigation of the AWU and police raids were legitimate.
"It's about testing whether or not hardworking union members money has been misused or abused," he told reporters.
"This is an investigation launched by the ROC, it's their investigation. It should run the proper course of the law of the land."
Crossbench senator Nick Xenophon wants to know how the media were tipped off about the raids.
"It smacks of a political sideshow and indeed a political witchhunt," he said.
"It does not speak well to the integrity of the Australian Federal Police if they are in anyway involved in that tip-off to the media."
The AWU will challenge the seizure of documents by the AFP in the Federal Court on Wednesday.
