Archbishop Aspinall has asked to be named as fifth defendant in a case launched by former Dean of Newcastle Graeme Lawrence and Cardiff priest Graeme Sturt after professional standards hearings in December.

The archbishop advised the court this week that he wanted to intervene in proceedings because the matters raised had general application to the operation of professional standards procedures in Australia.

In a statement of claim Father Lawrence and Father Sturt alleged the diocese had a case to answer over its handling of disciplinary hearings after the diocese investigated allegations against them of inappropriate behaviour with a child in the early 1980s.

Both priests denied the allegations.

They alleged the Newcastle diocese professional standards board was "affected by actual bias against" Father Lawrence and had prejudged the allegations against him.

They alleged the board denied both priests procedural fairness and made an error in law in drawing an inference that Father Sturt "must have known" about alleged misconduct of other priests.

Their case is against Bishop Farran and retired NSW magistrate and professional standards board president Colin Elliott, University of Newcastle chancellor and board member Trevor Waring, and board member Barbara Howard.

The priests have sought damages and an order to permanently restrain the bishop and the diocese from any future action over the original allegations made against them.

Solicitor John Woodward for the priests said: "The case is a significant one because it has the potential to affect the operations of professional standards investigations throughout the church in Australia."

The court will determine the archbishop's application in March.

A five-day hearing of the priests' case will start in May.