Gordon Smith is the affable Sheriff of Bradford County, home of the Florida State Prison. A Democrat, Smith appears genuinely concerned to represent the death penalty as a just and fair response to the most heinous crime. Admitting that it is "unfortunately not a deterrent", Smith nonetheless believes that there are some violent criminals for whom execution is the only acceptable form of punishment.

"It is a protection of our community," says Smith. "Some people are so evil that death is the only punishment to fit the crime." What about imposing a whole life tariff for dangerous killers? "There is always a risk that they may return, and death is final."

I ask the Sheriff about the apparent contradiction between his religious beliefs and supporting state executions. "Thou shall not kill is really, thou shall not murder," he replies. 

Does the death penalty give better protection against the most dangerous criminals? There is evidence that death sentences are haphazardly meted out, with virtually no connection to the severity of the crime. One study in Connecticut, conducted by John Donohue, a Stanford law professor, found that inmates on death row are indistinguishable from equally violent offenders who escape that penalty and that the process is often arbitrary and discriminatory.

I ask Gordon Smith if he worries about wrongful convictions. "Sometimes people are wrongly convicted, but we are going overboard in trying to protect innocent people and we have cared less and less about the victims of crime."

During my visit to Florida I repeatedly heard talk of the case of Trayvon Martin, a 17-year-old African American shot dead by George Zimmerman, a neighbourhood activist, in a gated community in Orlando last February. Zimmerman was not charged for more than a month because he invoked self-defence under Florida's so-called "stand your ground" law. This racially charged case has raised the question of discrimination once again. Studies have found that although blacks and whites are murder victims in nearly equal numbers, 80 per cent of prisoners executed were convicted of murders where the victim was white.