Paris Hilton was released from Century Regional Detention Facility in Lynwood, Calif. early Thursday because of an unspecified medical problem and will fulfill the reminder of her sentence in home confinement, a sheriff's spokesman said.

Entertainment Tonight is reporting the medical reason was actually a rash on her body. Her psychiatrist also visited her while she was in prison, with TMZ.com reporting that her psychiatrist told the sheriff she was was "fragile and at risk."

Hilton is not unique in playing up a medical condition with the hopes of getting out of work duty, or better yet, getting out of jail. While she may not be the first, she may be one of the most successful.

"It is an anomaly and a little disconcerting for the average person," said Gilbert Geis, professor of criminology, law and society at University of California, Irvine.

For most correctional facilities, Geis noted, the last thing they want to do is release someone into society who might have mental health issues.

Most facilities will treat a person within a facility, or transfer them to a hospital or medical health facility for treatment. There are many narcotic addicts who are very sick in prison he said, as well as very serious problems with hepatitis C and other chronic illnesses within prisons.

For the average person, there is one medical reason that can warrant release.

"If you have a terminal condition, you may get out, " Geis said. "If you have anything else you'll just have to limp along to the medical unit. You can only get out if you're totally incapacitated, like being terminal within six months."

But even for prisoners nearing death, release may only mean the confines of a hospital bed. Geis pointed to researchers who have a difficult time collecting numbers on prison deaths because so many dying prisoners are transferred to hospitals where the death is then registered as municipal.

In the case of Hilton, it is doubtful she will set a precedent for others to follow.

"Most medical releases depend on the facility, the seriousness of the medical condition and the likelihood that the person will violate the law again and hurt someone else," Geis said. "For a young woman, or any young person, this is very, very unusual."