You make some very interesting points. I guess my main argument against it is that almost all other well off democracies have gotten rid of the death penalty. There are years and years of data from these countries that show that the death penalty isn't necessary.
Absolutely right. That's why I used a fictional character to introduce that line of reasoning.
That was a lead up to a key pivot though: incarcerated individuals do not need to escape to attack others (inmates or guards). Death row prisoners in California have slashed at wrists and necks of guards using homemade razors for over a decade. Tim McGhee, a self-described "thrill" killer, cut and sent two bloodied guards to the hospital in 2012. Guard Timothy Davison was beaten to death by a prisoner in Texas just last year. Two convicted murderers killed 59-year old Susan Canfield in 2007 after overpowering another guard.
Better protocols and supervision can prevent some of these. Gang-related killings inside prison walls are too common too, but there are not as many easy response options there. People need to be allowed to socialize, but once you have people in a big group, they can harm each other.
There are several no-win scenarios in running corrections facilities.
As I said in the post, I oppose the death penalty, but I wouldn't find it unreasonable or "uncivilized" as the GP put it to be moved by these concerns (albeit in certain very limited situations).