A state corrections department analysis of a bill being considered by California lawmakers has found that mandating life sentences for some child molesters and lifetime parole for others would cost tens of millions of dollars annually after the first decade.

The nonpartisan Legislative Analyst puts the ultimate tab at hundreds of millions of dollars each year, some of it to build new cells for sex offenders serving longer terms.

The projections come as an Assembly committee prepares to consider on Friday whether the state can afford the bill introduced after a paroled sex offender's rape and murder of two Southern California teenagers.

Republican Assemblyman Nathan Fletcher of San Diego says his bill will have a relatively low cost for the first decade. He says it's worth the money to protect children.