Premenstrual syndrome in Sri Lankan criminal law:

Abstract

This study critically examines the possibility of introducing Premenstrual Syndrome (PMS) into the adjudication of criminal cases involving female offenders in Sri Lanka. The increasing use of syndrome-based evidence, particularly in relation to defences such as insanity and diminished responsibility, has generated considerable legal and medical debate. PMS, which explores the correlation between women’s menstrual cycles and behavioural, psychological and physical changes, has been judicially acknowledged in certain comparative jurisdictions. This study interrogates whether PMS or its severe variant, Premenstrual Dysphoric Disorder (PMDD), may fall within existing criminal defences under the Sri Lankan Penal Code, justify the creation of a separate defence, or instead operate as a mitigating factor. It argues that while severe PMS/PMDD may influence behaviour, they do not doctrinally satisfy the threshold requirements of insanity, unsoundness of mind, or automatism under Sri Lankan law. Accordingly, the most coherent and sustainable approach is to recognise medically substantiated cases at the sentencing stage as a mitigating factor.