It seems to me that when there’s a need to give members of a firing squad “plausible deniability” then it’s because someone on the squad knows it’s unethical to participate in the first place and therefore makes one more argument in favor of eliminating the death penalty altogether.

-It seems similar to an argument against using a paralytic in the lethal injection. If the immediate audience is too squeamish or shocked to participate in such events then it’s probably because those events shouldn’t be taking place.