A "historical lack of formal policies" and "cultural taboos" allowed child sex abuse committed by former American School in Japan teacher Jack Moyer to go unchecked for decades, an independent legal team tasked with probing the pedophilia scandal concluded in a long-overdue report Monday.

Responding to the report, the ASIJ board of directors conveyed in a community letter emailed to alumni Monday their "sincere and heartfelt apology" to victims of Moyer's abuse, renewing their vow to make "ASIJ a safe environment and a strong and united community."

Factors such as a "historical lack of formal polices and protocols for responding to allegations of sexual abuse," "a historical lack of awareness of issues pertaining to child sexual abuse generally" and "cultural norms that treated discussing sexual abuse as taboo" prevented the school from confronting Moyer and approaching law enforcement, the report said.