One of the maxims of criminal law orthodoxy states that a defendant’s motive for offending, be it good or bad, should have no weight in assessing his or her criminal liability—although it may rightfully bear on the punishment imposed. Known as the “irrelevance of motive principle,” this idea owes much of its popular stature in legal thinking to arguments that draw on the notion of the rule of law. It is said that allowing defendants’ motives to generate or negate their criminal liability would undermine the state’s authority in defining the contours of crime.
The article identifies and critically examines three streams of such arguments, and these in turn lead to three findings. First, each manifestation of the rule of law argument defends a somewhat different conception of the irrelevance principle; this means that despite the common allusion to the irrelevance principle, there is no singular principle, but instead several variants of the norm are at play. Secondly, rule of law arguments fail to sustain any meaningful notion of the irrelevance principle. Finally, there exists a sphere of instances where the careful application of motives to criminal directives may advance the rule of law by infusing legislation with added clarity and richness.