Yeah, with all the problems the US has had acquiring an appropriate cocktail of drugs for lethal injections over the last few years, you'd think someone would look into this kind of thing. Nitrogen is super easy to get.
I am not up to date with US lethal injection, but weren't the changes in lethal injections in the US "yeah, it's still a painful death, but we added muscle relaxants so it looks peaceful on the outside and acceptable to the public?"
I think there's always been a paralytic involved. The idea was to knock the person out with a barbiturate, then stop the breathing with the muscle relaxant, and finally stop the heart with a bolus of potassium chloride.
It's not so much to pretend it's peaceful, as it's a error in how the drugs are administered and availability of appropriate drugs.
This is exactly my point - why do something so complicated when many people die quietly in their homes from CO poisoning? Let's just setup a CO poisoning chamber to do the same thing.
Or nitrogen as the article describes. Or a fatal overdose of a pleasant drug like morphine?
Sadism, mostly. The electric chair was painful enough but too picturesque, which makes it easy to rally against. The injections solve that problem whilst still inflicting immense pain. Which is supposed to be good, because these damn criminals had it coming. Or something.
They've always used hydrogen cyanide (HCN) gas, typically produced from potassium cyanide pellets dropped into hydrochloric acid. Zyklon B is just HCN.
