It reinforces my belief that finding the culpits, understanding the situation that led to the death, and a fair trial, are all vital prior to sentencing.
There have been too many miscarriages of justice in this country to introduce a system that results in the death of more innocent people (who have been wrongly convicted). In your system not only will we see 'all criminals' going to prision even for petty offences, we will also see the execution of many innocent people.
Should the death penalty ever be reintroduce, all those who support it in any way will have the blood of innocent people on their hands.