A report prompted by sexual abuse allegations in the German Catholic Church accuses Pope Emeritus Benedict XVI of misconduct on four counts during his time as archbishop of Munich and Freising between 1977 and 1982.
Benedict — known then as Cardinal Joseph Ratzinger — has denied any wrongdoing.
Munich law firm Westpfahl Spilker Wastl (WSW) was asked to investigate allegations of sexual abuse in the Archdiocese of Munich and Freising between 1945 and 2019.
The report, commissioned by the archdiocese, said there were at least 497 victims of abuse.
Most of them were male children and adolescents who were targeted between 1945 and 2019, the law firm announced.
Many other cases had probably not been reported, the lawyers said.
A spokesman for the former Pope did not immediately respond to a request for comment.
Attention has focused on Joseph Ratzinger, later Pope Benedict XVI, who was Archbishop of Munich and Freising between 1977 and 1982.
Presenting the report for WSW, lawyer Martin Pusch said Ratzinger had done nothing against the abuse in four cases.
“In a total of four cases, we reached a consensus that there was a failure to act,” said Mr Pusch, adding the former Pope had “strictly” denied responsibility in response to the accusations.
Benedict, now aged 94, has been living in the Vatican since resigning as pontiff in 2013.
In a statement that did not mention the former Pope, the Vatican said it would evaluate the full report and examine its details.
“In reiterating a sense of shame and remorse for the abuse of minors by clergy, the Holy See assures its closeness to all victims and confirms the path it has taken to protect the little ones and guarantee them a safe environment,” spokesman Matteo Bruni said.
The WSW lawyers were tasked with finding out who knew what happened in the archdiocese and any action they took.
According to the study, there were at least 235 alleged perpetrators — among them 173 priests and nine deacons.
The law firm said 40 clergymen had returned to pastoral care despite allegations of perpetrating or having tolerated abuse.