Updated

The former Stanford swimmer convicted of sexual assault on an unconscious woman failed to reveal his drug and alcohol use in a letter to the judge.

Brock Turner told Judge Aaron Persky that he was an unexperienced drinker and that "the party culture and risk taking behavior" during his four months at Stanford led him to make a bad decision.

But court documents released Friday show prosecutors cited several examples of Turner using hard drugs and alcohol at Stanford and in high school.

Prosecutors say that text messages recovered from his cellphone showed Turner discussing using LSD and ecstasy and smoking marijuana and dabs of butane hash oil, known as "wax," from as early as April 2014.

Court documents also show campus police gave him a ticket for underage drinking in November 2014.