'This is pure nonsense': UCLA law professor explains the flawed logic of the judge who sentenced the ex-Stanford swimmer to 6 months in jail

Santa Clara County Sheriff's Office

Judge Aaron Persky's full sentencing decision in the case of Brock Turner, the 20-year-old ex-Stanford swimmer convicted of sexually assaulting an unconscious woman in 2015 was made public.

It's offers a glimpse into the rationale of the judge whose decision has been decried as a slap on the wrist.

Peter Arenella, a professor of law emeritus at UCLA, says the decision reveals that Persky relied on a deeply flawed argument to make his decision.

To begin his sentencing decision, Persky quoted from a letter written to the court by the victim of the sexual assault: 

"You should have never done this to me... But here we are. The damage is done, no one can undo it."

Persky used this as a launching point for his sentencing decision: 

"So, as she writes, the damage is done. And in my decision to grant probation, the question that I have to ask myself...Is state prison for this defendant an antidote to that poison? Is incarceration in state prison the right answer for the poisoning of [Jane’s] life? And trying to balance the factors in the Rules of Court, I conclude that it is not and that justice would best be served, ultimately, with a grant of probation."

Arenella says that Persky's reasoning has a "serious defect."

"This is pure nonsense and indicates that the judge doesn’t fully grasp the concept of giving defendant their just deserts," Arenella told Business Insider via email.  "He never addresses the need for the community to have a punishment that is proportionate to the severity of the crime committed."

Santa Clara County Sheriff's OfficeTurner was found guilty of felony sexual assault for a January 2015 attack on an unconscious woman. Two graduate students saw Turner assaulting a woman behind a garbage bin outside of a fraternity house at Stanford University. When he tried to run, the graduate students pinned him down until the police arrived.

Despite facing a maximum of 14 years in prison and prosecutors asking for 10 years, Persky sentenced Turner to six months in a county jail and three years' probation.

Detractors have accused Persky - also a star athlete during his time at Stanford - of bias in sentencing Turner. Arenella agrees.

"This sentencing judge erred in my opinion because of an unconscious class bias and a failure to give adequate weight to the severity of the crime and the defendant's great culpability in committing it in this manner," he said.

Since Turner's sentencing, more than 1 million people have signed petitions calling for the permanent removal of Persky, who was recently excused from another sexual assault case.