This chapter and the one that follows concern the two basic elements of the offence called ‘genocide’. Because genocide constitutes a criminal infraction, and because this study concentrates essentially on the law of genocide, a jargon familiar to criminal lawyers has been chosen for this discussion. To the criminal lawyer, the ‘elements of the offence’ are fundamental because they set out the ground rules of the trial, determining what must be proven by the prosecution for a case to succeed. If the prosecution establishes all the elements of the offence beyond a reasonable doubt (or the intime conviction) of the trier of fact, then a conviction may lie. If the defence casts reasonable doubt on even one ‘element of the offence’, then the accused is entitled to acquittal.

Criminal law analysis of an offence proceeds from a basic distinction between the physical element (the actus reus) and the mental element (the mens rea). The prosecution must prove specific material facts, but must also establish the accused's criminal intent or ‘guilty mind’: actus non facit reum nisi mens sit rea. The definition of genocide in the 1948 Convention invites this analysis, because it rather neatly separates the two elements. The initial phrase or chapeau of article II addresses the mens rea of the crime of genocide, that is, the ‘intent to destroy, in whole or in part, a national, ethnical, racial or religious group, as such’. The five subparagraphs of article II list the criminal acts or actus reus.