When a woman chose to be executed for her husband's crimes.
When a husband and wife who had spent years on death row were to be executed. The husband kidnapped, raped, and killed numerous young women over many years, while the wife is believed to have killed their infant son.
The BAU discovered that the boy is alive and well, and that the wife had given him up for adoption to save him from her dangerous husband. At the last minute, she begged the team to allow her to be executed and to not tell her son, now 16, who had a happy, successful life with his adoptive family.
Season 1, Episode 14 “Ride the Lightning”