My objection to capital punishment is the political component. There are (or have been) far too many politicos who have included in their platform support for, or against, the death penalty, often because it appeals to their base. I recognize that there are people whose death contribute to safety and security of society, or a specific community or country (i.e., there are people who deserve to be killed). Often they are external to a particular jurisdiction, may not necessarily be a named individual and their demise isn't as a result of judicial verdict. Nation states (usually) have little or no remorse in authorizing the killing of individuals as a result of extraterritorial military/security operations.
I suppose when we know the individual that we want to kill and approach it from a formalized, systematic approach it becomes more personalized. At that point there is usually political involvement, either an elected individual (or political appointee) who has input in the decision to seek the death penalty or to authorize the killing. The actual killing itself is delegated to a minor functionary, almost a washing of the political hands. Since Canada has long ago suspended the death penalty, the most frequent examples we see of politicians demonstrating their "tough on crime" bona fides are from south of the border.
The particulars of the story in the OP brings to mind the debate surrounding the execution, almost fifty years ago, of Gary Gilmour. His method of execution was also by firing squad. One of the things I remember about it was the large number of persons who, without solicitation, volunteered to be part of the firing party.
How Gary Gilmore's 1977 execution came to pass
time.com
In 1976, when Gary Mark Gilmore was sentenced to death by firing squad, TIME
reported that dozens of men were calling the Utah state prison warden asking to be one of the shooters.
The warden today said that he would draw the names from the list of volunteers after he had screened those who sought participation for “unhealthy” reasons.”
“I can't judge everyone's motive,” he sat. “and I'm not sure what criteria I should use In evaluation. I'm just lookin for solid citizens.”
Just as there were (are) persons who volunteer (participate?) in the execution of a death penalty for "unhealthy reasons", I'm sure that there are politicians who support the death penalty for political purposes despite the possibility of error in the verdict and the irreversible finality of the sentence. Since the deliberate taking of life by the state should be a major event, my suggestion is that the execution (regardless of method) should be performed by the senior responsible politician in the jurisdiction (e.g., Governor of the state, POTUS). Additionally, if error is later discovered that the verdict was flawed, then the individual who authorized and carried out the execution should then be prosecuted for the killing.
Yes, I'm aware that such will never come about, but I dislike hypocritical politicians.
