Australia's major union for construction workers, the CFMEU, has long been known as hardline in the way it went about its business.

But a couple of months ago, investigative journalist Nick McKenzie's stories revealed damaging accusations that the union, which regularly overseas government funded work sites had been infiltrated by organized crime. 

Even before the story broke on 60 minutes and in our mastheads, it triggered the resignation of the Victorian construction union boss John Setka. 

But Setka will not go without a fight, and last week, he appeared at prize government worksites to rail against the move to place the Union under administration. 

Today, Nick McKenzie on what the surprise appearance of the former Union boss means and what it will take to clean up the CFMEU.

Further reading:

- Nick McKenzie and The Age and The Sydney Morning Herald's 'Building Bad' series.