DYSON Heydon has delayed a decision on his future until Monday, when he will reveal if he will disqualify himself as royal commissioner overseeing the inquiry into trade union corruption.

The decision follows revelations in The Australian newspaper of further emails regarding Mr Heydon’s acceptance of an invitation to speak at a Liberal Party function in Sydney.

The ACTU has been given until 5pm on Friday to make written submissions regarding the emails.

Mr Heydon has not set a time for his ruling on Monday.

On August 12, the NSW Bar Association’s publications manager Chris Winslow received a phone call from former journalist and lawyer Marcus Priest expressing surprise at Mr Heydon’s acceptance of an invitation to speak at a Liberal Party function, the Sir Garfield Barwick address.

Mr Winslow then emailed Jeremy Stoljar SC, the counsel assisting the royal commission.

“Is Dyson Heydon aware that the Garfield Barwick Address, which he is due to deliver, is a Liberal Party fundraiser?” read the email, released to the ACTU on Thursday.

Mr Stoljar replied: “I’ll raise that with him (Heydon). Thanks.” Mr Stoljar did not show the emails to Mr Heydon but made a note of a meeting with the commissioner at 9am on August 13.

He wrote of the meeting that Mr Heydon had shown him an email from the event organiser, lawyer Greg Burton, which stated it is not a fundraiser.

“Burton is closer to the action than Winslow - he ought to know,” Mr Stoljar noted.

“So OK to go ahead if JDH (Heydon) writes clarifying + response OK.” In response to a query from the ACTU, James Beaton - the solicitor assisting the inquiry - downplayed the relevance of the material saying the commissioner “does not presently apprehend the relevant of the documents” to the issue of him standing aside from the commission. A

Mr Heydon was meant to hand down his decision tomorrow.

His decision will come a week after the ACTU, CFMEU and AWU already made submissions seeking the commissioner stand aside over perceived bias, because he accepted an invitation to speak at a Liberal Party event.

Mr Heydon has been considering his position, having already admitted he “overlooked” the connection to the political party when he agreed to give the Sir Garfield Barwick address.

The event was meant to be held on Wednesday night.

Prime Minister Tony Abbott has insisted the commission “must and will” keep going, even if Mr Heydon steps down.

Mr Heydon’s fate has continued to spark increasing speculation since he postponed a decision originally scheduled for yesterday, on whether he would stand down in response to claims he was biased against Labor and the union movement.

Mr Abbott referred to comments former Labor minister Martin Ferguson made on Four Corners this week, where he expressed his support for the commission to help stop corruption.

“This inquiry is not a political game, this inquiry is important for the future of the union movement and the Labor Party,” Mr Abbott said.

“So, regardless of what the royal commissioner ultimately decides, the royal commission must and will go on.”

On the ABC program, Mr Ferguson said: “I just don’t see the royal commission as a political play thing, I actually think it’s potentially going to be very important in reforming the trade union movement and the Labor Party and I will not damn it.”

Originally published as Heydon defers decision on his future