There are occasions when the death penalty may be the only way to protect the community from a particularly vicious criminal. There is also some evidence that states with the death penalty have lower rates of murder. So it is possible to make a pro-life argument in favour of the death penalty.

The death penalty should be on the table as an option of last resort, used very rarely.

But where a death sentence is imposed, very strong penalties need to apply when prosecutors deliberately withhold evidence that might help the defence. In fact, there should be severe consequences for prosecutors and others who abuse due process even when the death penalty is not an option.

The New York Times has John Thompson’s frightening story:

I spent 18 years in prison for robbery and murder, 14 of them on death row. I’ve been free since 2003, exonerated after evidence covered up by prosecutors surfaced just weeks before my execution date. Those prosecutors were never punished. Last month, the Supreme Court decided 5-4 to overturn a case I’d won against them and the district attorney who oversaw my case, ruling that they were not liable for the failure to turn over that evidence — which included proof that blood at the robbery scene wasn’t mine.

Because of that, prosecutors are free to do the same thing to someone else today. …

The prosecutors involved in my two cases, from the office of the Orleans Parish district attorney, Harry Connick Sr., helped to cover up 10 separate pieces of evidence. And most of them are still able to practice law today.

Why weren’t they punished for what they did? When the hidden evidence first surfaced, Mr. Connick announced that his office would hold a grand jury investigation. But once it became clear how many people had been involved, he called it off.

In 2005, I sued the prosecutors and the district attorney’s office for what they did to me. The jurors heard testimony from the special prosecutor who had been assigned by Mr. Connick’s office to the canceled investigation, who told them, “We should have indicted these guys, but they didn’t and it was wrong.” The jury awarded me $14 million in damages — $1 million for every year on death row — which would have been paid by the district attorney’s office. That jury verdict is what the Supreme Court has just overturned. …

Worst of all, I wasn’t the only person they played dirty with. Of the six men one of my prosecutors got sentenced to death, five eventually had their convictions reversed because of prosecutorial misconduct. Because we were sentenced to death, the courts had to appoint us lawyers to fight our appeals. I was lucky, and got lawyers who went to extraordinary lengths. But there are more than 4,000 people serving life without parole in Louisiana, almost none of whom have lawyers after their convictions are final. Someone needs to look at those cases to see how many others might be innocent.