Julie Watts Reporting

SACRAMENTO (CBS13) — Of the 737 inmates on death row, 49 are from the Sacramento area including Scott Peterson, who was convicted of killing his pregnant wife Laci Peterson in 2002. Also on death row is Lonnie Franklin, aka the Grim Sleeper, who was convicted in 2016 of killing nine women and a teenage girl in Los Angeles.

The last person executed in California was Clarence Ray Allen in 2006.

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One of the driving factors to get rid of the death penalty is the high cost of inmates on death row. Many studies over the years found the death penalty system costs more than life in prison as the maximum penalty, but no one seems to know specifically how much more an inmate costs on death row.

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The Governor’s office says the state spends $150 million a year for people on death row, but they could not say how that cost compares for the same inmates moved into the general prison population.

Instead, the office pointed to an analysis of a 2016 ballot measure which found the state could save around $150 million annually by abolishing the death penalty, but said that number could vary by “tens of millions” pending various factors.

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The Department of Corrections said they don’t know the cost difference either. The state only tracks the average cost of all inmates, combining death row and the general population.

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Last year, the average inmate cost around $80,000 to $700,000 a year. That cost includes security, housing, food, and medical care.

Medical costs for aging inmates also have to considered as well. Those can get so high that Governor Brown signed a bill making it easier to parole inmates over the age of 60. Analysts found they cost two to three times more than the average inmate.

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Death row inmates will not be eligible for parole, but the longer they live in prison, they will cost exponentially more. According to the most recent death report, the average life expectancy for death by natural causes for inmates was 62-year-old. The oldest inmate to die that year was 91.