When I examined the cost of Florida’s death penalty many years ago, I concluded that seeing a death sentence through to execution costs at least six times as much as a life sentence. A more recent study by a federal commission pegged the difference in the costs of the trials at eight times as much. Duke University professor Philip J. Cook studied North Carolina’s system and concluded that the Tar Heel State could save $11 million per year by abolishing the death penalty. California’s system incurs excess costs estimated at some $200 million per year . From Kansas to Maryland , Tennessee to Pennsylvania , studies have all reached similar conclusions.