Conflicting ideas about justice and public safety, underlined by economic considerations, emerged in a public forum Sunday on two state ballot measures that would abolish the death penalty and amend the three strikes law.

"If it's not broken, you don't fix it," child safety advocate Marc Klaas said, asserting that California's three strikes law has "worked superbly" since voters approved it in 1994, a year after his daughter, Polly, was abducted from her Petaluma home and murdered by a repeat offender.

"You have half the chance of being the victim of a violent crime than we did in 1994," Klaas told about 150 people attending a forum called "Changing Criminal Justice in California" at Congregation Shomrei Torah in Santa Rosa.

Richard Allen Davis had been sentenced to more than 200 years in prison before he killed Polly, her father said, but knew he would be released in a few years in each case.

"He wanted to avoid AIDS by getting a young one," Klaas said in an impassioned presentation, wearing a button with 12-year-old Polly's face on it.

Steve Fabian, a Santa Rosa criminal defense attorney and American Civil Liberties Union board member, said Proposition 36 on the Nov. 6 ballot is a "very limited fine-tuning" of three strikes.

It would require that a third strike, triggering a sentence of 25 years to life, must be for a serious or violent crime rather than any felony, as the law now stipulates.

Of the 8,873 third strikers currently imprisoned in California, more than half — 4,676 — were convicted for nonviolent crimes such as drug possession and shoplifting, Fabian said.

Three strikers account for 6.6 percent of the state's 134,868 prison inmates, and Klaas said they are "absolutely and exactly where they need to be."

"No rapists or murderers will benefit from Proposition 36," Fabian said, noting that convicts would be eligible for re-sentencing only if their third strike was nonviolent; none of their prior convictions were for rape, murder or child molestation; and a judge determined they were not a threat to public safety.

The current law is unfair, costs too much and has not made California safer, Fabian said, citing the state Legislative Analyst's estimated $70 million to $90 million annual savings from amending three strikes.

Violent crime rates had already peaked before the law was passed, Fabian said, attributing the decline to an aging population, not three strikes.

Sonoma County has 27 three-strikers in prison, he said.

District Attorney Jill Ravitch, who moderated the forum, said it is "rare if ever" that her office seeks a third strike penalty for a nonviolent offense.

Ravitch said she is not taking a public position on either Proposition 36 or Proposition 34, which would repeal the death penalty as the maximum punishment for murder and replace it with life imprisonment without parole.

Life sentences give society "every bit of protection" it could ask for without risking "the cost of executing innocent people," said Lawrence Marshall, a Stanford University law professor who supports the ballot measure and was co-founder of the Center on Wrongful Convictions at Northwestern University.

"You are better off being guilty and rich than being innocent and poor," he said, noting the prevalence of minorities on death row and in the criminal justice system overall.

Marshall also disputed the idea that capital punishment deters crime, saying that "people who do murders do it because they think they won't get caught or they just don't care."

About 900 people have been sentenced to death in California since 1978, and 14 inmates have been executed — none since 2006. Eighty-three inmates have died prior to execution, and 75 have had their sentences reduced, leaving 726 on death row.

Kent Scheidegger, an attorney and legal director of the Criminal Justice Legal Foundation, noted that Virginia executed Beltway sniper John Allen Muhammad six years after his conviction.

"We could do that here," Scheidegger said, asserting that every defendant should receive only one appeal and appeals should be terminated when no "claim of innocence" is raised.

The death penalty "costs more than it needs to," he said, but the cost estimates fail to include the prosecutorial savings when capital murder cases are plea-bargained down to life without parole as well as the medical expenses involved in keeping people incarcerated for life.

The Legislative Analyst estimated a savings of $100 million to $130 a year from abolishing the death penalty.

"It really shouldn't be about the money," Scheidegger said. "We can afford justice, and we should continue to do so."

Marshall said he has worked on death penalty cases in which exonerating evidence emerged 14 to 18 years after trial.

"They are us, they're our children," he said, referring to murderers. "We are a community."