The Thirty Nine Articles said: "The Laws of the Realm may punish Christian men with death, for heinous and grievous offences".
Lambeth 1988, Resolution 33" "Urges the Church to speak out against: ... all governments who practice capital punishment, and encourages them to find alternative ways of sentencing offenders so that the divine dignity of every human being is respected and yet justice is pursued";
There are at least (and in reality there were a lot more) twenty four people we could name executed in the Henry VIII period who were clearly executed on grounds and evidence which would not stand up to any standard of justice we would imagine today.
For example, of the 16th of January 1542 an act was passed that made it a treasonable offence for an unchaste woman to marry the King without revealing it. On that day Katherine Howard (his fifth wife) was then arrested and executed on the 13th of February 1542.
One of the great problems with capital punishment is that by it the state does that which cannot be undone, and indeed in the case of a mistake there is little in the way of meaningful redress for the person who has been executed.
We have enough history, and we have enough wisdom, to know that this is not a good thing. Even with the best will in the world, even the fabulous legal system of the United States of America can (and I imagine does) make mistakes. If we need to resort to capital punishment as our only means of redress, I suspect that we pass judgment on ourselves as a society as much as we pass judgment on the offender.
Genesis 9:5-7
For your own lifeblood I will surely require a reckoning: from every animal I will require it and from human beings, each one for the blood of another, I will require a reckoning for human life. Whoever sheds the blood of a human, by a human shall that person’s blood be shed; for in his own image God made humankind. And you, be fruitful and multiply, abound on the earth and multiply in it.’
I get that I can argue for the death penalty from scripture. Yet I also find inspiration in scripture for a yet more excellent way.
John 1:4-5
in him was life, and the life was the light of all people. The light shines in the darkness, and the darkness did not overcome it.