County jail, not state prison, is ahead for San Francisco resident Jennifer Leigh Prince, who was arrested in December 2010 in connection with five Portola Valley property crimes, including two auto burglaries and three thefts in the Brookside Park neighborhood.

Superior Court Judge Lisa Novak sentenced Ms. Prince, 41, a nine-time inmate in state prison, to three years of incarceration. Prosecutors had asked for five years.

But with a new state law enacted in 2011 reserving prison for violent offenders, local courts now have options that were unavailable under the old system, prosecutors said.

In the case of Ms. Prince, Judge Novak on Jan. 6 split her three-year sentence into two years and eight months in jail, with the potential to serve that time in a residential treatment program, and four months of parole-like supervision by the county, according to the San Mateo County District Attorney's Office.

Such a split would not have been possible under the old system, Assistant District Attorney Al Serrato said in a telephone interview. The court is doing "things we've never done before," he said.

Ms. Prince had pleaded no contest to three felony counts: possession of stolen property, identity theft, and burglary. She is subject to fines totaling $430, restrictions on weapons possession, abstention of alcohol and drugs, testing for substance abuse, and the loss of Fourth Amendment rights regarding search and seizure, and restitution to victims, prosecutors said.

As a reward for good behavior, Ms. Prince will receive credit of 757 days, leaving her about 7 months of incarceration, which she may serve in residential treatment if the judge agrees. Inmates can earn credit for activities such as working while in jail, pursuing a high school diploma, and undergoing counseling.

The case unfolded after an incident on Dec. 23, 2010, shortly before 6 a.m., when sheriff's Deputy Todd Finato walked over to investigate a green Jeep Cherokee occupied by two women and parked on Crescent Avenue in Portola Valley's Brookside Park neighborhood.

Deputies had been called about an auto burglary on Canyon Avenue a few blocks away.

Deputy Finato obtained the identity cards of the two women and happened to notice a piece of property similar to one reported stolen in the Canyon Avenue incident. At that point, the driver put the Jeep into gear and fled the area, deputies said.

Deputy Finato gave chase but lost sight of the Jeep, which had no license plates, deputies said. Three Brookside Park thefts and another burglary were later reported for Dec. 23.

San Mateo police happened to stop Ms. Prince at 3:40 a.m. on Dec. 24 for a traffic matter, and she gave the police an ID card later found to have been stolen in Grass Valley, deputies said.

Investigators from the San Mateo Police Department consulted with Sheriff's Office investigators and determined that Ms. Prince had been driving the Jeep in the Dec. 23 case.

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