Heydon to mull over commission future

Dyson Heydon will spend the weekend deciding on his future as the trade union royal commissioner after hearing submissions calling for his resignation.

The retired High Court judge at the helm of the long-running unions royal commission was told on Friday he had no choice but to recuse himself from the inquiry.

The barrister for the union body leading the apprehended bias charge, the ACTU, told the hearing Mr Heydon's status as a "truly brilliant" jurist would leave fair-minded onlookers mystified as to how he could have failed to latch on to the nature of a Liberal Party event he had agreed to address.

Earlier this week, Mr Heydon said he had overlooked the political dimension of the event despite a back-and-forth email trail that noted the annual Sir Garfield Barwick memorial lecture attendees had been warned to disclose political donations, and that funds raised would go to NSW Liberal coffers.

The commission may reconvene on Tuesday, when Mr Heydon hopes to have an answer on his future.