Why I’m fighting on against the death penalty (Cherie Blair)

As former President George W Bush knows, I rarely waste an opportunity to press the case against the death penalty.

In his recently published memoirs, he recalls a heated debate between us over capital punishment which, to my husband's discomfort, threatened to derail an informal dinner at Chequers.

It's why I wish every success to the lawyers trying to outlaw the export of a drug used in lethal injections in the US.

Whether or not they can convince the court to overturn Business Secretary Vince Cable's refusal to add sodium thiopental to the list of banned goods — and they face big hurdles — the case highlights the continued use of the death penalty across the world. It also shows why we can't be satisfied with having abolished the death penalty in the UK.

The international balance is shifting slowly against capital punishment. Two more nations last year formally abolished the death penalty, taking to 95 the number which no longer have it on their statute book. Many of those who retain it no longer carry out executions. Russia, for example, has extended its moratorium. Amnesty International says last year was the first when not a single person was executed across all of wider Europe.

The campaign against capital punishment has been bolstered by a growing international case law which argues that it breaches basic human rights.

But those of us who object to the death penalty on essential moral grounds must also be ready, if we are to persuade those who support capital punishment, to argue that it is both ineffective and the cause of some terrible miscarriages of justice.

There is increasing evidence to undermine the argument that capital punishment somehow acts as a deterrent. In the United States, for example, the 35 states which retain it have consistently higher murder rates than those which don't.

This leaves punishment and retribution as the most powerful argument in its favour. It is why the recent spotlight on miscarriages of justice is having an increasing impact on the debate in the US. Last month, a Texan facing execution had his conviction overturned — the 12th person in the state to be exonerated on death row since 1973.

Figures for the US as a whole are even more shocking, with 139 people sentenced to death later found innocent. After the 13th such case in Illinois, the state Governor blocked any further executions.

It is easy to understand why there are so many miscarriages of justice in capital cases. The death penalty is reserved for the most horrific and senseless crimes. These are the very cases which produce the strongest anger and outrage among investigators, prosecutors, judges
and public. Both are emotions which make a mistake all the more likely in the determination to see a crime punished.

My argument with President Bush, who was happy to defend his own views, was ended by my son suggesting I had said enough. But while he was probably right given the occasion, the international fight against the death penalty is too important for us to remain silent.

The threat by Iran to stone Sakineh Mohammadi Ashtiani has rightly united world opinion in outrage. But we have to be ready to keep up the pressure to see capital punishment abolished wherever it is still used.