This chapter focuses on the social construction of gender-based fatal violence—femicide—through the legal field. Doing so, it uncovers and exposes gender-based biases hidden beneath supposedly “neutral” laws, identifying the gender-based consequences that such laws create. One such doctrine that appears gender neutral yet plays a major role in the construction of gender-based lethal violence is the British doctrine of provocation assimilated in all ex-British colonial states, under which the subsequent American doctrine of heat of passion originated and flourished. This legal doctrine contributed to the gendered social belief that a wife’s infidelity is an extraordinary affront to her husband’s sense of self and manhood, resulting in the mitigation of the criminal liability of men accused of murder in circumstances of possessiveness toward their female intimate partner. The American heat of passion doctrine further extended the criminal mitigation offered by the British doctrine by focusing on judging the killing that the defendant perpetrated from a subjective, rather than an objective, point of view. Such a doctrine applies a partial criminal defence for crimes committed under the influence of alleged intense emotions, regardless of provocation immediately before the act of homicide, and enables a broad subjective component designed to remove the act of homicide from the scope of the offence of murder. Consequently, the American doctrine of provocation in the heat of passion is highly forgiving toward intimate partner femicide perpetrators and may, although inadvertently, tolerate and even encourage femicide.