No. Never. Under no circumstances.
Killing another human can only be justified in the most extreme cases of self-defence when there are no other options available.
With convicted criminals the option of incarceration is always an available alternative thus making state-sanctioned murder totally unjustifiable.
Furthermore no judicial system is infallible. If someone is wrongfully incarcerated he can always be released and receive an apology and a compensation if he turns out to be innocent. If he's dead there is nothing you can do to make up for the wrongful killing.
"What is a thief? - A thief is someone who covets his neighbour's property so much that he doesn't take the time to form a corporation."
"The poor complain - they always do
but that's just idle chatter.
Our system brings rewards to all
- At least to all who matter."
"It is good that things have gotten better but it would be better if things were good."