California corrections officials have increased scrutiny of paroled sex offenders, a move that follows years of failures in how Phillip Garrido, now accused in the kidnapping of Jaycee Lee Dugard, was monitored.

A policy that took effect Thursday calls for parole agents to check records of GPS tracking for offenders who are on "passive" monitoring.

Those offenders wear GPS monitoring devices. Previously, the records of their whereabouts were checked only if a crime had been committed or questions arose about an offender's movements, said corrections spokesman Oscar Hidalgo.

Under the new policy, such offenders will have two consecutive days of movements randomly checked twice a month.

The policy is designed to ensure that offenders know their movements are being checked, Hidalgo said, and stems from the Garrido case.

Garrido, a convicted rapist and kidnapper, was on parole and living in his mother's Antioch home in 1991 when Dugard was kidnapped from the South Lake Tahoe area at age 11.

Dugard was discovered 18 years later living with Garrido, and corrections officials came under scrutiny for their lax monitoring of him and their failure to discover Dugard.

As a result, corrections Secretary Matthew Cate promised a series of improvements in how parolees - particularly sex offenders - are supervised.

Higher-risk sex offenders are tracked through what corrections officials call "active" monitoring, meaning their movements for each previous day are checked daily.

As of March 1, corrections officials said there were 2,219 offenders on passive monitoring in California and 4,779 on active monitoring.