Transgression:
an act of transgressing; violation of a law, command, etc.; sin. [Dictionary.com]
Not a word I run across real often, and I decided I wanted a precise definition when I saw it in this: “On Supreme Court politics, McConnell counts on short memories,” Steve Benen, Maddowblog:
It worked: McConnell effectively stole a Supreme Court seat from one administration and handed it to another. He’s repeatedly boasted about the pride he takes in having executed the transgressive scheme.