Pattern of utilization of the insanity plea in Nigeria: An empirical analysis of reported cases

• Main Authors: A. Ogunwale, O. Oluwaranti
• Format: Article
• Language: English
• Published: Elsevier 2020-11-01
• Series: Forensic Science International: Mind and Law
• Subjects: Pattern; Insanity; Plea; Cases; Nigeria; Defence
• Online Access: http://www.sciencedirect.com/science/article/pii/S2666353820300035

There is dearth of information about the pattern of utilization of the insanity plea in Nigeria and the factors associated with its successful adoption. This enquiry is important in order to bridge the gap in existing knowledge on the subject in Nigeria and possibly other parts of Africa. Using a manual search of all reported judgments from appeal cases since 1948, thirty-four cases adopting the insanity plea were obtained. The rate of plea success was 26.5% (n = 9) with most defendants being males. Psychotic disorders were most commonly diagnosed (5/11, 45.5%) among the defendants. The main ingredient of plea success was either loss of capacity to control action or understand conduct. Limb 1 (Cramer's V = 0.57, p = 0.007) and unfamiliarity with the victim (Cramer's V = 0.44, p = 0.036) were very strongly associated with a Not guilty By Reason of Insanity (NGBRI) verdict. This study concludes that the insanity plea is successful in a modest number of cases. The crime, plea and defendant characteristics provide guidance for defendants seeking to adopt the plea and offer mental health experts valuable insight into the relevant medico-legal information in the expert opinion that may avail an accused person an effective insanity defence where morally justified.