Philip Wilson, archbishop of Adelaide, is preparing to step aside from his duties after the New South Wales court of appeal unanimously dismissed his latest attempt to have a charge of failing to report child abuse quashed.

A spokeswoman for archbishop told Guardian Australia. “Now that there has been clarification on some of the points of law which arise, the archbishop is keen to move onto the trial preparation phase and will take time away from his duties when the trial approaches so that he can prepare his defence and demonstrate his innocence.”

Wilson is the most senior Catholic in the world to be charged with failing to report child sex abuse. He stood aside in March 2015 after a magistrate held he had to stand trial but resumed duties in Adelaide early last year as his legal team continued to fight through the courts.



The archbishop has now failed at every hurdle. The magistrate, a supreme court judge and now three members of the court of appeal – including the chief justice of NSW Tom Bathurst QC – have all found that the archbishop must stand trial.



The court’s decision opens the way for the NSW director of public prosecutions to bring charges against a number of other Catholic priests and officials, as well as leaders of other faiths for failing to volunteer what they know to police.

Wilson was newly ordained and in his first parish in 1976 when, it is alleged, a 15-year old boy told him he had been sexually assaulted by the local priest, Jim Fletcher. This was in Maitland, NSW. Later that year Wilson allegedly heard the same thing from a child in confession: he, too, had been assaulted by Fletcher.



Wilson did not call the police.



Fletcher continued to abuse children for nearly 30 years in various parishes in the Hunter Valley until he was finally arrested and convicted in 2004 on nine charges of assault and aggravated indecency. More victims came forward but Fletcher died of a stroke in prison in 2006 without facing further trials.



The church gave him a splendid send off attended by the local bishop Michael Malone, the vicar-general of the Maitland-Newcastle Diocese and 31 priests. They prayed for his soul. He was buried a priest.



Wilson was not present for the occasion. While Fletcher’s career had gone from bad to worse, Wilson had flown upwards through the ranks to become, in 2001, the Archbishop of Adelaide. As the youngest Catholic bishop in the country great things were predicted for him. He was seen as Cardinal material.



But Wilson had a problem. NSW has preserved an ancient law that makes it a crime to fail to report a crime – not any crime, but serious indictable offences which citizens know or believe to have been committed. This is set down in section 316 of the NSW Crimes Act.

No section of any NSW criminal law has been as closely studied from every possible angle by lawyers for the Catholic church. On a broad interpretation it threatens with prison every church official who, when told a priest has been abusing children, hasn’t picked up the phone to tell the police.

NSW authorities came for Wilson in 2015. They weren’t complaining about him failing to help the police all those years ago in Maitland. He was charged with failing to come forward to the police with what he knew about other victims after 2004 when Fletcher was arrested and facing trial.



In the words of the court attendance notice: “Philip Edward Wilson … believing that [Fletcher] committed that offence and knowing he had information which might be of material assistance in securing the prosecution of [Fletcher] for that offence, without reasonable excuse, failed to bring that information to the attention of a member of the NSW police force.”



None of the prosecution claims against Wilson have been tested in court. Since early 2015 the archbishop’s lawyers have been arguing he should never face trial because the state of the law in NSW and the nature of the evidence – even if true – would mean any proceedings against him were “foredoomed to fail”.



Every court has so far disagreed.



Two key questions in their judgments have profound implications for the church. The first is oddly theological: what is belief?



Wilson argued that two boys telling him they had been assaulted by a local priest could perhaps raise suspicion but not belief as required by section 316, not “without more”.



Judge Monika Schmidt of the NSW supreme court found the prosecution’s dossier of evidence against Wilson could – if proved – establish far more than mere suspicion and also that Wilson had not forgotten what he heard from those boys in Maitland in 1976.



“The victim’s allegations were about repeated offending of the most serious kind, involving masturbation, oral and other sexual assault of a young child by a priest, contrary not only to law, but it may reasonably be inferred, contrary to the teachings of the Catholic church … it may also be inferred that this was not a commonplace experience for the archbishop at that time, but an unusual one.”



The judge said that the prosecution would present evidence of Wilson’s shocked response to the two boys and assurances he gave that their allegations were being investigated. The judge declared the claims – if proved - were “capable of giving rise to the inference that the allegations about [Fletcher’s] offence were allegations the Archbishop remembered in 2004”.



At trial the prosecution would argue that belief came to Wilson when he learned more about Fletcher’s crimes after that date.



The judge set out the prosecution’s claim that after Fletcher’s arrest, the archbishop “learned from various people known to him about other similar alleged offending in the same parish by [Fletcher] against two other young victims; that he then counselled another priest about his obligations to report such complaints to the police; and that [Fletcher] was convicted of offences against one of those victims, before his death in 2006”.



None of this has been proved but the judge concluded the police case was not doomed to fail but was “capable of giving rise to an inference that in 2004 the requisite belief as to [Fletcher] having offended against the first victim in 1971 was formed by the archbishop”.



That is not a good verdict for the church. While it remains open for Wilson to argue that he never believed those boys despite all they are alleged to have told him and all he later learned about Fletcher, the NSW Supreme Court has refused to set within narrow bounds the law’s understanding of belief.



The second key question Wilson took to the court of appeal mattered even more to the church. This was a claim of immense technical complexity that various bits and pieces of law reform in NSW over the last 30 years have, perhaps inadvertently, decriminalised the concealment of historic offences.



Had the court accepted Wilson’s argument, then no church official would ever face charges in NSW of concealing crimes committed by priests through the worst years of the church shunting paedophiles from parish to parish.



The court unanimously dismissed the argument. The three judges found that Fletcher’s crimes in the 1970s fell squarely within the ambit of section 316 of the Crimes Act. Wilson, they concluded, has to stand trial.



That no judge has come to the aid of the Archbishop of Adelaide at any stage makes an appeal to the high court very unlikely. The law seems settled: priests and bishops, headmasters, imams and rabbis remain answerable in NSW even today for beliefs about paedophiles they never took to the police.



Wilson is accused of believing one priest assaulted two boys. The royal commission into institutional responses to child sexual abuse has heard evidence of Catholic officials in NSW knowing of dozens of victims of dozens of priests – and never picking up the phone to call the police.

The penalty for concealing serious crimes in NSW can be imprisonment for up to two years.