Updated 1.15pm

Former pope Benedict XVI failed to stop four clergymen accused of child sex abuse in the Catholic Church in Munich, the law firm that carried out a key probe said on Thursday.

The ex-pontiff - who was the archbishop of Munich and Freising from 1977 to 1982 - has "strictly" denied any responsibility, said lawyer Martin Pusch of Westpfahl Spilker Wastl which was tasked by the church to carry out the probe.

But the experts do not consider this credible, he added.

Two of the cases involved clergymen who had committed several proven acts of abuse but were allowed to continue with pastoral duties, Pusch said. 

An interest in the abuse victims was "not recognisable" in Benedict, he said. 

In one case, a now-notorious paedophile priest named Peter Hullermann was transferred to Munich from Essen in western Germany where he had been accused of abusing an 11-year-old boy.

Hullermann was reassigned to pastoral duties despite his history.

In 1986, by which time Benedict had been transferred to the Vatican, he was convicted of molesting more children and given a suspended prison sentence.

Even after the conviction, he continued to work with children for many years and his case is regarded as a pertinent example of the mishandling of abuse by the Church.

The ex-pope has denied knowing about the priest's history, but the lawyers said they were now convinced this was not the case.

Pusch said the pope emeritus had initially shown a "defensive attitude" when responding to questions for the report. However, he later changed his attitude and gave a detailed written statement.

Cardinal Reinhard Marx, the current archbishop of Munich and Freising, was also found to have failed to act in two cases of suspected abuse.