An investigator commissioned by a famous German boys' choir says that more than 200 children in the choir were abused physically and sexually between 1953 and 1992, many by the director of an affiliated school; the choir itself was led between 1964 and 1994 by Georg Ratzinger, a priest whose brother Joseph served as Pope Benedict XVI from 2005 through 2013, and the investigator says he "must assume" that Georg Ratzinger had at least some knowledge of the abuse. Ratzinger is not accused of committing any of the alleged crimes.
The Regensburg Domspatzen choir hired a lawyer named Ulrich Weber in 2015 to investigate the allegations, which were first reported publicly in 2010. From the Religious News Service:
Benedict’s brother, Monsignor Georg Ratzinger, conducted the historic choir from 1964 to 1994. Asked if Ratzinger, now 92 and still living in Regensburg, had known of the abuse, Weber said: “After my research, I must assume so.”
“The events were known internally and criticized, but they had almost no consequences,” Weber said. The cases are too old to be prosecuted, he said.
The New York Times notes specifically that Weber says "a 1987 investigation of reported abuse did not prompt the choir’s leaders to remove Mr. Meier or take other action."
Roughly a quarter of the alleged abuses were sexual in nature. From AFP:
[Types of abuse] ranged from sexual assault to rape, severe beatings and food deprivation, said Weber.
"The reported cases of sexual abuse in Regensburg were mostly concentrated in the period of the mid to end 1970s," he said, adding that "50 victims spoke of ten perpetrators".
The director and composer Franz Wittenbrink, a former pupil of the boarding school, had told Spiegel magazine in 2010 that there was an "system of sadistic punishments connected to sexual pleasure".
Benedict/Ratzinger—who now lives in retirement at the Vatican—was accused before and during his tenure as pope of playing a key role in the Catholic Church's cover-up of its priests' crimes and of the role that Church bureaucrats played in letting molestation and abuse go unpunished.