I oppose the death penalty, but if countries are going to impose it, then the firing squad is a pretty decent method. It’s rapid and painless enough not to be sick torture, but it’s also brutal enough to remind everyone concerned that they are, actually, violently and prematurely ending a life.
Which is good, because that’s what the death penalty involves, whether or not you personally support it. You’re either saying “it is right for the state to violently and prematurely end this person’s life for the good of society/justice”, or you are saying “it is not right for the state to violently and prematurely end people’s lives”.
Shooting – as with UK-style hanging by the days of Albert Pierrepont – doesn’t try and cover up the fact that a human being is being violently killed, whilst also not revelling in the person’s suffering (unlike, say, crucifixion or stoning). Lethal injections and gas chambers, by removing the element of violence and disguising the taking of a life as a medical or scientific procedure, are no more humane than shooting or hanging – but far more dishonest and hypocritical.
If firing squads turn your stomach because they involve killing a person, then that’s all to the good. But don’t kid yourself that any of the other methods of execution are any better.
Well, apart from the one administered to Arthur Charles Herbert Runcie MacAdam Jarrett (unbelievably, not available on YouTube), of course.