According to prison and parole officials, the rules have changed since Phillip Garrido won parole on a Nevada rape conviction in 1988.
Garrido is now charged with kidnapping, raping and imprisoning Jaycee Dugard for the past 18 years. She was just 11 when she was forced into a car near her south Tahoe home in 1991 while waiting for a school bus.
Before that, Garrido served 11 years for the rape of a South Lake Tahoe casino worker in 1976. But he was paroled by both federal authorities and Nevada parole officials.
According to David Smith of the Parole Board, there were major changes in Nevada's criminal sentencing laws as well as parole rules between 1995 and 2000 that make it much tougher, especially for sex offenders, to get out of prison.
In the 1995 session, then-Sen. Mark James of Las Vegas spearheaded a major revision of criminal penalties in Nevada, pushed by the "truth in sentencing" guidelines at the federal level.
The result was tougher penalties and longer sentences for major crimes including rape. In addition, Smith said sex offenders must pass a psychological screening by a panel of psychologists using standardized assessment tools. Their job is to determine the risk that inmates might commit another sexual offense.
"We know a lot more about sex offenders today than we did 20 years ago," he said.
As a result, fewer rapists win parole from their life sentences these days.
"People should understand that the parole board seriously reviews cases of inmates who are serving sex offenses or have prior convictions for sex offenses before making the determination they should be released," said Smith.
He said even if a convicted rapist wins parole, he doesn't just go free. Major sex offenses such as rape and lewdness with a minor carry life sentences and require lifetime supervision by parole and probation if they are ever released.
In the past six months, Smith said the parole board has held more than 4,100 hearings for inmates, including 357 sex offenders. Of those, 79 received parole. Sex offenders made up less than 4 percent of parolees during that period.
He said a good share of those parolees were in for crimes such as statutory sexual seduction, indecent exposure and failure to register as a sex offender - none of which carries a life sentence. Some were paroled because their sentence is nearing its end and parole allows the state to continue monitoring them beyond that time.
In addition, he said some involved inmates who were paroled from one sentence to another sentence and, therefore, weren't released from prison.
Director of Corrections Howard Skolnik said partly as a result of the tougher laws, about 40 percent of Nevada prisoners have some level of sex offense in their history. It could be a relatively minor offense such as indecent exposure when the inmate was young. But he said that is still documented in their record.
Skolnik said the 2007 Legislature changed good time credits to get more of the minor, non-violent offenders out of prison to relieve crowding. Those changes, he said, didn't give the additional credits to category A and B felons - the categories for most serious sex crimes.
He described the 1970s and 1980s as "the feel good years."
"The laws aren't the same," he said. "There's a lot more attention being paid to them than there used to be. The laws today, the length of time and the nature of sentences are much greater than they were in the 1980s."
Skolnik said Nevada's tougher parole system appears to be working since the parole violation rate for those who are released is only about
8 percent.