Last month’s school shooting in the suburbs of Denver, Colorado, claimed the life of an innocent child. Eight more were injured. In the way that this crime affects the victims and their families, the tragedy is similar to many previous incidents. But it also uniquely highlights a criminal justice challenge that has been the subject of debate: what to do with transgender criminals? In the UK, where prisoners are classified primarily according to a policy of “self-identification,” recent controversy has focused on Karen White, a violent transgender woman who was moved to a male facility in 2018 after being accused of sexually assaulting multiple female prisoners. In the United States, where prisoners generally are classified according to their biological sex, the issue has been less prominent. However, that may soon change. One of the two suspected shooters in Colorado is listed in court records as Maya McKinney, a 16-year-old female. However, the suspect now identifies as “Alec,” and has asked that male pronouns be used in all official proceedings—even though Alec is being housed in …