For a long time, many researchers have been attracted to the hypothesis that females who develop antisocial behaviour surmount a higher threshold of risk than males and are therefore more severely afflicted. This hypothesis goes by many names, including group resistence, the threshold effect, and the gender paradox. Because the hypothesis holds such wide appeal, it is worth revisiting the logic behind it. The hypothesis is built on the factual observation that fewer females than males act antisocially. Because this is true, then the deduction is made that some factor has raised the threshold that females must pass before they convert antisocial attitudes, feelings, or motives into actual antisocial actions. A higher threshold implies that the few females who have indeed passed their high threshold were pushed over it by stronger causes than were the males who passed their low threshold. Generally the female threshold is presumed to be raised by gender-role socialization of females against aggression, at the level of the culture. The push over the threshold is presumed to come from psycho-biological or developmental factors, at the level of the individual. The hypothesis is typically addressed empirically by comparing the strength of aetiological variables across groups of antisocial females and males, looking for evidence of more severe aetiology among females. If more severe aetiology is found for girls, then the inference is made that a higher threshold for girls exists.

The criminologist Thorsten Sellin (1938) referred to this line of reasoning as the ‘group resistence’ hypothesis.