Death penalty question, whether you are for or against it: Why not switch from lethal injection to the guillotine?

The drugs used in lethal injections are becoming very difficult to obtain in the US, and as a result states are more and more turning to “experimental” and illicitly obtained drugs. To add to this, there have been problems with the previously used three-drug cocktail when it was not injected properly, causing inmates to suffer prolonged and horrific deaths, or sometimes not die at all – just suffer.

On the other hand, the guillotine is quick, painless and 100% effective. Isn’t that everything an execution should be?