California Inspector General Investigating Phillip Garrido's Parole Oversight

California's inspector general has launched an investigation into one of the most mystifying questions in the kidnapping case of Jaycee Dugard: How was accused kidnapper Phillip Garrido able to keep her hidden for 18 years with police and parole officers assigned to check on him?

Inspector General David Shaw told today that while the investigation only became public this week, it began "almost immediately" after Dugard, now 29, and the two children believed to be fathered by Garrido, were rescued.

It is believed Garrido, 58, had five or six different state parole officers assigned by the California Department of Corrections and Rehabilitation over the 18 years he imprisoned Dugard in his backyard, Shaw said. He was forced to register as a sex offender after being convicted of the rape and kidnapping of a woman in California in the 1970s.

The investigation is twofold, Shaw said. First, "to see whether there was any misconduct on the part of any CDCR employee" and also to examine the system to see where improvements can be made statewide.

Gordon Hinkle, spokesman for the CDCR, told that the inspector general's investigation was "understandable" and that the department has already turned over all records relating to Garrido.

"We welcome their review and are doing our own internal review as well," he said.

Shaw said he couldn't comment on any preliminary findings but said a full report, which will be made public, is expected within 30 days. Five investigators are assigned to the case.

Shaw told ABCNews that his first reaction to Jaycee Dugard's rescue was "shock that this could have gone one for so many years without being discovered."

Shortly after Dugard was rescued, Hinkle praised the unidentified parole officer who investigated Garrido after two UC Berkeley police employees spotted him with children on the school's campus and found that he was a registered sex offender.

Erika Price Shulte, a spokeswoman for Dugard and her family, told that the family did not have any comment on any aspect of the investigation. Dugard, she said, remains in seclusion and the reunion with her family continues to go well.

Garrido and his wife, Nancy, have pleaded not guilty to 28 charges, including kidnapping and rape. Garrido is being held on $30 million bond. Nancy Garrido's attorney has not requested bail.

Sheriff Admits Responsibility for Not Rescuing Jaycee Dugard

How a registered sex offender with rape and kidnapping convictions was able to keep an 11-year-old girl in his backyard and father two children with her has been the question many have been asking from the start.

State parole officers and police are known to have paid Garrido and his wife Nancy visits to their Antioch, Calif., home. As recently as 2006, an officer with the Contra Costa Sheriff's Office was called to the house on a complaint from a neighbor that there might be people living in the backyard.

The officer met with Garrido in his front yard, determined there was no threat and left.

At a press conference in August, Sheriff Warren Rupf took responsibility for the incident and noted that they were not aware of Garrido's sex offender status.

"He did not enter or request to enter the backyard. This is not an acceptable outcome. Organizationally, we should have been more inquisitive, more curious and turned over a rock or two," he said at the time. "I cannot change the course of events. But we are beating ourselves up over this and will continue to do so."

Hinkle said the 2006 incident was cause in itself for review of communications between the state and local jurisdictions -- Garrido's parole officer at the time was never notified of the complaint.

Garrido had also been routinely visited throughout the years by a task force set up to check on sex offenders.

Much of the blame in the case at this point seem to rest on manpower: Overwhelmed police officers and parole officers who have dozens or hundreds of felons to check on in a state that has been besieged by budget shortfalls.

Hinkle said parole officers are assigned to sex offenders on a 40 to 1 ratio statewide, unless the offender has been designated as a "sexually violent" predator, in which case the ratio shrinks to 20 to 1.

Garrido, he said, was not classified as a sexually violent predator.

Hinkle said that while there have not yet been any changes to CDCR's policies relating to parole checks or sex offenders, it's likely lessons have already been learned.

"As for a mind-set, I'm sure a lot of parole agents are learning what they can from his case," Hinkle said.

Sex Crimes Expert: 'There Could Be Blame All Around'

Carl Wicklund, executive director of the American Probation and Parole Association, said the lack of manpower is endemic to the country as a whole.

"Ideally somebody should have known what's going on," he said of the Dugard case. "It's a clear indicator of an overstretched system that does not have adequate personnel to supervise people in the community."

It's not just the number of offenders that parole and probation officers have to keep track of. It's the paperwork that goes along with each visit and keeping an eye on those with electronic monitoring bracelets, those who need drug tests and those that have been ordered to pay restitution.

"The workload itself can be pretty daunting," he said.

In an ideal situation, he said, a parole officer wouldn't just visit the offender, but walk their home and the property's grounds while also poking around for pornographic materials and computer evidence.

Stacey Honowitz, a sex crimes expert and an assistant district attorney for the state of Florida, said in many cases all a parole officer is assigned to do is check to make sure the sex offender is living where they say they are.

"That's unfortunately where the ball got dropped," she said.

But in a country that is "inundated with sex offenders," Honowitz said its the responsibility of the community as a whole to keep track of them. She urged everyone to know who is living in their neighborhood and to keep an eye out for anything suspicious.

"It's just a matter of who you blame in this case," she said. "There could be blame all around."