Life on death row: Florida State Prison where the electric chair was the sole means of execution from 1924 until 2000  

Florida State Prison, in the small town of Starke, is a sprawling mass of gray concrete and barbed wire, approached by a road lined with palm trees and lush greenery. "This is what I call the green mile," says my guide Rosalie Bolin, "but at the end of it is hell." The prison houses death row and the execution chamber.

On the green mile we pass a hearse that, she tells me, is used exclusively by the prison. "No one wants to have their loved ones in a vehicle that has carried murderers," she says. "People see them as inhumane, and that is how they are treated, even in death."

Bolin has been involved in preparing mitigation arguments for defendants in capital cases for more than 20 years. There are currently 400 men and four women on death row in Florida and I am visiting Starke to explore America's shifting opinion on capital punishment. 

Capital punishment was suspended in the US from 1972 to 1976. Since the suspension was lifted, 1,280 people have been executed, most since 1990, though only 78 death sentences were passed in 2011, compared to 312 in 1995. Since 1973 more than 130 people have been released from death row after their convictions were overturned. From 2000-11, exonerations have averaged five a year. 

A majority of Floridians support the death penalty and opinion, unsurprisingly, is divided along political and religious lines. Three-quarters of Republican voters support state execution compared to just under half of Democrats. Catholics oppose the death penalty more than non-Catholics. Age is also a factor: Americans under the age of 30 are less likely to support the death penalty.