I'm pretty sure that that is not true.
Instead you'll be issuing more apologies to families of the wrongfully accused that are now dead at the hands of the government.
Then what's with all that talk about psychopathy? Psychopaths do not commit murders out of circumstance.
I wouldn't be surprised if executions happened much more frequently in the dark ages. I'd certainly consider it more akin to the "dark ages" than putting someone in a cell.
The death penalty does not serve as a deterrence, and I feel allowing it sends the wrong message to the rest of society.
Furthermore, a disproportionate number of murder convicts that get executed tend to be both poor and from minorities. People without high quality legal counsel (i.e. public defenders) tend to have juries and judges consider their crimes more worthy of execution moreso than those that can afford higher quality attorneys.
The judicial system is not perfect, and can never be perfect. And unless it is perfect, I'd never support the death penalty.