California's "three-strikes" sentencing law has incapacitated thousands of repeat felons, appropriately so. But the 1994 law also has led to disproportionately long sentences for individuals whose third strike was for a petty crime.

Proposition 36 would sand down some of the law's rough edges and ensure that it is applied equally across all 58 counties, but leave the law's strong heart in place. It deserves a "yes" vote Nov. 6.

In 1994, voters enraged by the kidnap-murder of 12-year-old Polly Klaas by a repeat felon approved the initiative that created the three-strikes sentencing law. Courts have softened it somewhat, but this state's three-strikes law remains the nation's harshest such measure.

Under the law, judges must impose sentences of 25 years to life for people who are convicted of two violent or serious crimes and who then commit a third felony, regardless of what that third felony is. Serious and violent criminals deserve harsh sentences. But individuals who commit petty crimes on their third strikes end up with sentences far in excess of what is fair.

Their incarceration comes at a cost. The Legislative Analyst's Office estimates that Proposition 36 would shave $70 million to $90 million off the $9 billion annual prison budget.

Voters rejected an attempt to water down three strikes in 2004. Proposition 36 is much more modest.

As it is, three strikes doubles sentences for criminals who are convicted of a violent or serious felony, and commit another felony. About 33,000 of the 138,000 inmates are serving enhanced sentences under this provision. Proposition 36 would not affect second-strikers.

Another 9,000 inmates are serving sentences of 25 years to life after being convicted of two violent or serious felonies, plus a third felony.

Some third strikes were serious or violent. Others were minor, such as shoplifting. If voters approve the measure, felons would need to commit a violent or serious felony before facing a three-strikes sentence.

People convicted of three burglaries – a serious crime – would face 25 years to life, as three-time losers convicted of a combination of violent crimes such rape, sex crimes involving minors, robbery, homicide, attempted murder and many others.

Under Proposition 36, about 3,000 of the 9,000 third-strikers serving 25 years to life would be eligible to file petitions to have their sentences reviewed by judges.

Los Angeles County District Attorney Steve Cooley, the Republican candidate for attorney general in 2010 and hardly a bleeding heart, is one of its main backers. He argues that disparate treatment by county prosecutors could subject the three-strikes law to a constitutional challenge. The numbers certainly vary.

The California Department of Corrections and Rehabilitation reported last year that Sacramento County, with a population of 1.4 million, had sent 565 individuals to prison on three-strikes sentences. Orange County, which has more than twice Sacramento County's population, had sent 392 felons away on three-strikes sentences.

Opponents say the three-strikes law has led to the drop in California's crime rate. But there are many reasons for the falling crime rate, including tougher gun restrictions and demographic shifts.

We are under no illusion that if voters approve Proposition 36, some felons who would face lesser sentences will commit other crimes. But locking up petty criminals who have no history of violent crimes for 25 years or more is fundamentally unfair, and far too costly.

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