Judge Roy Ellis was asked to consider if prosecutors proved beyond reasonable doubt that Wilson, 68, failed to disclose allegations about priest Jim Fletcher between 2004 and 2006 after police charged Fletcher with crimes against a Hunter boy in the 1990s.

Judge Ellis ruled in Wilson's favour, quashing his convictions in a decision handed down on Thursday in Newcastle.

Wilson was the Bishop of Wollongong from 1997 to 2000. 

In May Wilson became the most senior Catholic clergyman in the world to be convicted of a conceal offence involving another priest. Newcastle Local Court Magistrate Robert Stone found Wilson – a former Hunter priest and Adelaide Archbishop – was told in 1976 of allegations against Fletcher.

The court heard evidence from two men that they reported child sex allegations to Wilson in 1976. Magistrate Stone found Wilson formed a belief that the allegations were true.

But in an appeal hearing in November Judge Ellis challenged barrister Helen Roberts for the Crown about whether Wilson had taken the “reasonable position of having an open mind about the allegations, so that he would not have reported them to police until he had a strong belief they were true.

During the trial Wilson said he had no memory of allegations being raised with him in 1976. Wilson also argued his belief about the truthfulness of allegations was based on “either an admission or on the conclusion of a trial”.

Magistrate Stone sentenced Wilson to 12 months’ jail – to be served as a minimum six months home detention at a relative’s home on the Central Coast – after rejecting that argument.

He found Wilson was “hiding behind a ‘formal view’ of what ‘belief’ means in a criminal context”.

Judge Ellis earlier said it could also be argued it was a “reasonable position” that Wilson “did not have to form a belief about it”.