The one-time Stanford swimming star whose six-month term for sexual assault sparked national outrage walked out of jail with his bowed Friday, after serving just half of his sentence.

Brock Turner refused to acknowledge the media after serving just three months for sexually assaulting an unconscious woman in a case that drew widespread condemnation.

The former Olympic hopeful swimmer walked out of the main entrance of the Santa Clara County jail Friday shortly after 6 a.m. local time and got into a white SUV. Turner, 21, who plans to head to his native Ohio to live with his parents, must register as a sex offender for life and faces three years of supervised probation.

Santa Clara County Sheriff Laurie Smith said Turner was given a large packet of hate mail on his release. She said he was held in "protective custody" during his incarceration, but that her department didn't receive any credible threats. "There was a lot of hate," she said.

Turner was convicted of assaulting the young woman near a trash bin after they drank heavily at a fraternity party in January 2015. He plans to appeal.

In the June sentencing, Santa Clara County Judge Aaron Persky cited the "extraordinary circumstances" of Turner's youth, clean criminal record and other considerations. He followed the probation department's recommendation for a "moderate" jail sentence.

Following backlash and a push for a recall, Persky voluntarily removed himself from hearing criminal cases, starting next week.

In her statement, the victim had described how the attack left her emotionally scarred.

"My independence, natural joy, gentleness, and steady lifestyle I had been enjoying became distorted beyond recognition. I became closed off, angry, self-deprecating, tired, irritable, empty," she said.

After Turner's sentence was announced, District Attorney Jeff Rosen said he was disappointed in its length.

"The punishment does not fit the crime," Rosen said in June. "The sentence does not factor in the true seriousness of this sexual assault, or the victim's ongoing trauma. Campus rape is no different than off-campus rape. Rape is rape."

In an editorial, the San Jose Mercury News had called the six-month county jail sentence "a slap on the wrist."

"Brock Turner's six-month jail term for sexual assault of an intoxicated, unconscious woman on the Stanford campus last year is a setback for the movement to take campus rape seriously," the newspaper said.

Jail inmates in California with good behavior typically serve half their sentences. Ohio prison officials earlier this month agreed to take over supervision of Turner's probation.

Greene County Sheriff Gene Fischer said Turner has five days to register as a sex offender with his office in Xenia, Ohio, 15 miles east of Dayton. He will have to report to a probation officer for three years and must avoid alcohol and drugs during that time.

Fischer said his department will send postcards to Turner's neighbors informing them that a convicted sex offender is moving in nearby. Turner will be required to register every three months in person at the sheriff's office, reaffirming that he is still living with his parents, the sheriff said.

Deputies also will check on Turner periodically and without warning to ensure he has not moved out without permission from authorities.

Turner also is barred from parks, schools and other places where children are expected to gather.

"He will be treated no differently than any other sex offender we monitor," Fischer said.

The Associated Press contributed to this report.