The reality show star, who checked into a women's jail at 3:15 p.m., was released at 4:37 p.m. "based on her sentence and federal guidelines," Los Angeles County Sheriff's Deputy Maribel Rizo said without elaborating.
Under a federal court mandate to manage jail overcrowding, arrestees sentenced to 30 days or less for a nonviolent offense are usually released within 12 hours, the sheriff's department said in a statement.
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Under the guidelines, Richie was "treated in the same manner as other inmates with a similar sentence," the statement said.
Richie, 25, was originally sentenced to 96 hours in jail, but that was reduced to 90 hours because of time served when she was arrested.
Richie arrived at jail with her attorney Shawn Chapman Holley and her boyfriend, Good Charlotte singer Joel Madden. Her time at the Century Regional Detention Facility was spent getting booked, including taking a mugshot and submitting her fingerprints, Holley said.
She didn't reach her jail cell.
"She was really treated like any other inmate," Holley said. "I think every inmate in her position, with that type of charge, would have been treated as she was."
Just hours before Richie did her time, Lindsay Lohan was charged with seven misdemeanor drunken-driving and cocaine charges for two arrests in the last four months. Attorney Blair Berk arranged a plea bargain and Lohan was sentenced to one day in jail, 10 days of community service and must complete a drug treatment program. She was also fined and placed on 36 months probation.
Richie served her 82 minutes at the county jail in suburban Lynwood, the same place her "The Simple Life" co-star Paris Hilton was housed for nearly three weeks after she was convicted of driving on a suspended license while on probation for an alcohol-related reckless driving case.
Richie was arrested on Dec. 11, 2006, after witnesses reported seeing her black Mercedes-Benz sport utility vehicle headed the wrong way on a freeway in Burbank. The California Highway Patrol said they found her parked in the car pool lane.
Richie pleaded guilty in July to a misdemeanor DUI charge in a deal with prosecutors that helped her avoid a potential year in jail because it was a second driving-under-the-influence conviction.
Her first conviction was in 2003 for driving under the influence of alcohol.
Richie, the daughter of Lionel Richie, told authorities after being arrested in December that she had smoked marijuana and taken the prescription painkiller Vicodin, a CHP officer said at the time. No drugs were found on her or in her car.
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