It's almost beyond belief. Over the weekend it was revealed that the leader of the Catholic Church in Ireland, Cardinal Sean Brady, was deeply implicated in a cover-up of serious sex abuse by a priest.

And not just any priest, but Father Brendan Smyth, the most outrageous child abusing priest this country has ever seen. The Irish Voice featured a front page story a few weeks back about the horrors he inflicted while he was in the U.S.

Brady, who has been telling his fellow bishops here recently that they should resign if they had been part of the cover-up culture in the Catholic Church over the years, has now been revealed as the master of the cover-up himself.

In his defense he is saying it happened 35 years ago, when standards were different, and he is pleading the Nuremberg defense -- he was only following orders. But his position is completely untenable, and the calls for his resignation are now deafening.

He is still saying he will only resign if called on to do so by the Pope. But by the time you read this he may already have gone.

It's the biggest crisis ever to face the Catholic Church here since the sex abuse scandals began to emerge.

Smyth caused the first and certainly the most notorious of the pedophile priest scandals in Ireland. He became famous not only because of the number of children he abused and the severity of the abuse, but also because a seven-month delay in extraditing him to Northern Ireland to face charges there resulted in the collapse of the Fianna Fail-Labor government in 1994.

The infamous case literally brought down the government and also caused a national outcry. The bulging-eyed, crazed face of the unrepentant Smyth was splashed across the media for weeks, and the controversy meant that he became emblematic not only of the depravity within the church, but also of the secrecy which had allowed abusing priests to operate.

And this was the pervert who Brady played a role in protecting almost 20 years earlier. Of all the nauseating priest abusers, Smyth was one of the worst and certainly the most infamous.

In 1975, the then Father Sean Brady was a priest in his 30s, a professor of theology and a rising young man in the church. At time he was also a secretary to the bishop of Kilmore, in whose area Smyth had been abusing.

Brady was sent to interview two of the young people involved. He believed their stories and sent a report to the bishop. He also, as was customary in such situations, got the victims to sign an oath of secrecy.

Having passed the matter up the line, he did nothing else. He did not report the matter to the Gardai (police) even though the story of abuse he heard was likely to have been severe. (Another 10-year-old boy who was abused by Smyth around the same time said this week that the priest was an aggressive pervert who had anally raped him five minutes after meeting him for the first time.)

In spite of the stories he must have heard from the two children, Brady did nothing except write his report for the bishop and wait for the matter to be dealt with internally by the church. The bishop banned Smyth from some priestly duties in his diocese, like hearing confessions.

But further action was left to the abbot of the religious order to which Smyth belonged. Effectively little happened, although even at that time Smyth had been the subject of numerous complaints and had clearly been abusing for a number of years.

Nothing effective was done to stop him and he went on to abuse dozens more children here, in Northern Ireland and in the U.S. over the next 20 years. The prolific offender later admitted a litany of sex attacks on about 90 children in the north and south of Ireland over a 40-year period; he died in jail in 1997.

The problem for the now Cardinal Brady is that if he had stepped outside the church system and canon law for a moment back in 1975 and reported what he had been told to the Gardai, Smyth could have been stopped. Instead Smyth was free to abuse for almost two more decades.

Brady's attempts over the past few days to justify how he acted back then have only made matters worse and have caused outrage among people all over Ireland. He said it was not up to him at the time to try to stop Smyth.

"Yes, I knew that these were crimes, but I did not feel that it was my responsibility to denounce the actions of Brendan Smyth to the police,” he said. "Thirty-five years ago we were in a different world. We had no guidance, we were in uncharted territory.

“Now we have higher standards, thankfully. Certainly I would not act in the same way now as I did then."

If that was an apology, it was half-hearted. What Brady is saying is that he had to do what his bishop at the time told him to do, and he had to follow the canon law system that kept things secret and did not involve the state authorities.

In effect what he is saying is that he had to “follow orders”-- the Nuremberg defense. But the Nuremberg defense did not work for the Nazis on trial, and it certainly won't work in this situation.

Brady was morally bound to sidestep what his superiors were doing and go to the police. But, like almost everyone else in the Catholic Church at the time he failed to do so.

How much that culture of secrecy has changed is also put into question by Brady's actions since then. His involvement with the Smyth cover-up has only come to light now because of an impending High Court case involving one of Smyth's victims. But the case has been coming for over 10 years and was kept quiet.

In this case, Brady is being sued in his personal capacity -- as well as in his role as head of the Catholic Church in Ireland -- by a woman who as a child was raped by Smyth over five years. She was one of those forced to swear an oath that she would not discuss meetings she had with clergy, including the then Father Sean Brady, about her allegations that she was abused by Smyth.

The woman in the case maintains Brady was one of three priests who interviewed her as a teenager, and failed to ensure it was reported to the state authorities. It is understood an affidavit submitted to the High Court accuses Brady of failing to report the formal signed complaints to Gardai, and of failing to take any adequate steps to ensure Smyth did not continue to perpetrate sexual assaults.

Of course, neither Brady nor the church accept that what happened in the Smyth case and in the cases of other abusing priests was a cover-up. They were dealing with it in the way laid down by the Catholic Church at the time, they say.

But the secrecy involved and the failure to involve the state authorities in matters that were criminal does amount to an effective cover-up.

So far, Cardinal Brady says he sees no reason to step down. "Frankly I don't believe that this is a resigning matter," he told reporters at the weekend.

"I insist again I did act and acted effectively in that inquiry (when the children were interviewed) to produce the grounds for removing Father Smyth from ministry."

But removing Smyth "from ministry" was not what was required. What was required was removing him from contact with children and from society, preferably by putting him in jail.

Also indicative of the instinctive secrecy which surrounds all this is the fact that, according to church sources, Brady did not tell Pope Benedict about the impending High Court case during the two days of talks between the Pope and the Irish bishops in the Vatican last month. Which seems odd since he is also saying that he will not resign unless asked to do by the Pope.

But then the Pope has his own problems, since he himself is implicated in the cover-up of child abuse by a priest when he was archbishop of Munich in the late seventies and early eighties. Instead of handing the priest over to the police, the then Archbishop Ratzinger sent the pedophile priest for therapy after he had been accused of forcing an 11-year-old boy to perform oral sex.

The priest was moved around and went on to re-offend, and in 1986 was convicted of child abuse, one of many priests who were involved in child abuse in Germany at the time. The German bishops issued a public apology recently for what had gone on at the time -- and this was a time when the present Pope was a major figure in the Catholic Church in Germany. So maybe he won't be calling for Cardinal Brady's resignation any time soon.

One thing seems clear now. The Catholic Church has lost all credibility and moral authority not just in Ireland but in Rome as well.