Depravity Scale, defining evil?

“Judges and juries both across the United States and in other countries who decide that a crime is “depraved,” “heinous,” or “horrible” can assign more severe sentences. Yet there is no standardized definition for such dramatic words that courts already use.” … “To minimize the arbitrariness of how courts determine the worst of crimes, and to eliminate bias in sentencing, the Depravity Scale research aims to establish societal standards of what makes a crime depraved”

WTF?