Mere factual innocence is no reason not to carry out a death sentence properly reached.
When is conduct a crime, and when is a crime not a crime? When Somebody Up There -- a monarch, a dictator, a Pope, a legislator -- so decrees.
Fast closed with double grills And triple gates–the cell To wicked souls is hell; But to a mind that's innocent 'Tis only iron, wood and stone.
The uneven impact of actual enforcement measures tends to mirror and reinforce more general patterns of discrimination (along socioeconomic, racial and ethnic, sexual, and perhaps generational lines) within the society. As a consequence, such enforcement (ineffective as it may be in producing conformity) almost certainly reinforces feelings of alienation already prevalent within major segments of the population.