A new analysis of the death penalty's costs says that taxpayers have spent more than $4 billion on capital punishment in California since it was reinstated in 1978, or about $308 million for each of the 13 executions carried out since then, the Los Angeles Times' Carol Williams reported Monday.

The examination of state, federal and local expenditures for capital cases, conducted over three years by a senior federal judge and a law professor, estimated that the additional costs of capital trials, enhanced security on death row and legal representation for the condemned adds $184 million to the budget each year.

The study's authors, U.S. 9th Circuit Judge Arthur L. Alarcon and Loyola Law School professor Paula M. Mitchell, also forecast that the tab for maintaining the death penalty will climb to $9 billion by 2030, when San Quentin's death row will have swollen to well over 1,000.

In their research for "Executing the Will of the Voters: A Roadmap to Mend or End the California Legislature's Multi-Billion-Dollar Death Penalty Debacle," Alarcon and Mitchell obtained California Department of Corrections and Rehabilitation records that were unavailable to others who have sought to calculate a cost-benefit analysis of capital punishment.