The question about how he went unnoticed became more pressing Friday when Garrido came under suspicion in the unsolved murders of several prostitutes in the 1990s, raising the prospect he was a serial killer as well. Several of the women's bodies - the exact number is not known - were dumped near an industrial park where Garrido worked during the 1990s.
Authorities acknowledged that they blew a chance three years ago to rescue Dugard from the backyard labyrinth of sheds, tents and outbuildings that were concealed from the outside world.
A neighbor called 911 in November 2006 and described Garrido as a psychotic sex addict who was living with children and had people staying in tents in his backyard.
The investigating officer spent a half-hour interviewing Garrido on his front porch but did not enter the house or search the backyard, Contra Costa County Sheriff Warren E. Rupf said. The deputy, who did not know Garrido was a registered sex offender even though the sheriff's department had the information, warned Garrido that the tents could be a code violation before leaving.
"We missed an opportunity to bring earlier closure to this situation," Rupf acknowledged. "I cannot change the course of events but we are beating ourselves up over this and continue to do so."
"We should have been more inquisitive, more curious and turned over a rock or two."
It was not the only missed opportunity.
As a parolee, Garrido wore a GPS-linked ankle bracelet that tracked his every movement, met with his parole agent several times each month and was subject to routine surprise home visits and random drug and alcohol tests, California Department of Corrections and Rehabilitation spokesman Gordon Hinkle said.
The last unannounced visit by a team of local police agencies was conducted in July 2008. Paramedics also were summoned to the house five times since 1999, presumably to help Garrido's 88-year-old mother, who had dementia.
"There was never any indication to my knowledge that there was any sign of children living there," Hinkle said.
As it turns out, Dugard and her two children were living there as prisoners, authorities say. The heavily wooded compound was arranged so that people could not view what was happening, and one of the buildings was sound-proofed and could only be opened from the outside.
Neighbors knew there were children living there. Damon Robinson has lived next door to the Garridos for more than three years and his then-girlfriend in 2006 told him she saw tents in the backyard and children. "I told her to call police. I told her to call right away," he said. Dugard, now 29, was reunited with her family and said to be in good health, but feeling guilty about developing a bond with Garrido over the years. Her two children, 11 and 15, remained with her.
"Jaycee has strong feelings with this guy. She really feels it's almost like a marriage," said Dugard's stepfather Carl Probyn, who was there when little Jaycee was snatched from a bus stop in 1991.
Probyn has been in constant contact with Dugard's mother, his ex-wife Terry Probyn, since she found out her daughter was alive on Wednesday.
Probyn said both mother and daughter are trying to avoid the public eye for now. After not seeing each other for 18 years, Dugard greeted her mother by saying, "Hi, mom, I have babies," according to Probyn. Dugard had her two daughters with her at the reunion, and it appears she never told them she was kidnapped by their father, he said.
She is now free thanks in large part to two quick-thinking police employees at the University of California, Berkeley who came across a rambling Garrido this week, with Dugard's two daughters in tow. He was on campus because he wanted to hold some sort of religious event.
Garrido seemed incoherent and mentally unstable, and the girls wore drab-colored dresses, were unusually subdued, had an unnaturally pale complexion and appeared robotic and rehearsed when they spoke, said Lisa Campbell. They said they were home-schooled by their mother and had a 29-year-old sister at home.
Colleague Ally Jacobs ran a background check on Garrido and notified his probation officer. On Wednesday, Garrido arrived at the probation officer's building with his wife, the two girls and a woman who initially identified herself as Allissa. She turned out to be Dugard and investigators said Garrido confessed to the kidnapping.
The authorities say they do not yet know whether she ever tried to escape or to alert anyone of her whereabouts, but she had chances to escape Garrido, who did a stint behind bars during the period of captivity.
Garrido and his wife pleaded not guilty Friday to a total of 29 counts, including forcible abduction, rape and false imprisonment. Phillip Garrido appeared stoic and unresponsive during the brief arraignment hearing. His wife cried and put her head in her hands several times.
Garrido gave a rambling, sometimes incoherent phone interview to KCRA-TV from the county jail Thursday in which he said he had not admitted to a kidnapping and that he had turned his life around since the birth of his first daughter 15 years ago. He told the television station that he walked into the FBI's San Francisco office on Monday with Dugard's daughters and dropped off several documents containing rambling passages about religion, sexual compulsion and mind control.
FBI spokesman Joseph Schadler confirmed Garrido left the documents with the agency, but declined to discuss any further details.
Garrido was required to register as a sex offender because he was convicted in 1977 of kidnapping a 25-year-old woman from parking lot in South Lake Tahoe, the same town Jaycee Dugard lived in when she was snatched from a school bus stop.
He was convicted of raping the woman multiple times at a Reno storage unit that the investigator from the case described as a "sex palace." It featured various sex aids, sex magazines and videos, stage lights, wine, and a bed, said investigator Dan DeMaranville.
Gail Powell, spokeswoman for the Nevada Department of Public Safety, said Garrido met his wife while he was serving time for the rape at the federal penitentiary in Leavenworth, Kan.
He served about 10 years of a 50-year federal sentence for kidnapping, and less than a year for a concurrent Nevada sentence of five years to life in prison for sexual assault. He was paroled in 1988, said Nevada Department of Corrections spokeswoman Suzanne Pardee.
A violation of Garrido's parole conditions sent him back to federal prison from April to August of 1993. Dick Carelli, spokesman for the federal Office of Court Administration, did not know what Garrido did to violate parole. Authorities are trying to piece together how and by whom Dugard was held during Garrido's four-month absence.
Hinkle said the alarm raised by the neighbor who contacted the sheriff's department never was relayed to Garrido's parole agent. But there was no ban on him having contact with children, nor restrictions on his travels.
Monica Adams, 33, whose mother lives on their street, said she knew Phillip Garrido was a sex offender and that he had children living with him. Other neighbors knew, too, but they assumed police were keeping tabs on him.
"He never bothered any one, he kept to himself," Adams said. "What would we have done? You just watch your own."
Probyn said he was frustrated to find out that a car matching the description of the one he saw speeding Dugard away in the day she was kidnapped was found in the yard of Garrido's home. Nancy Garrido also fits the "dead-on" description he gave of the woman who pulled her into the car, he said.
"He had every break in the world," Probyn said of Garrido's close encounters with the law.
Associated Press Writers Don Thompson in Sacramento, Terence Chea in Berkeley, Paul Elias in San Francisco, Juliet Williams in Placerville, Michelle Rindels in Orange, Calif., and Martin Griffith in Reno, Nev., contributed to this story.