The Ongoing Debate Surrounding the Fitness to Plead

The Ongoing Fitness To Plead Debate

The Ongoing Fitness To Plead Debate

Fitness To Plead Overview

The debate surrounding the ‘fitness to plead’ remains largely one of the most controversial and highly scrutinised issues within the criminal justice system to date. Originating from early concepts of crime and punishment derived from Aristotelian principles in the 4th century BC, a variety of legislative reforms and historical developments have since paved the way for a new era of contemporary legal frameworks surrounding mental capacity, and fitness to plead in court. Today, fitness to plead centres upon the basic premise that vulnerable individuals must be protected in court, by determining the capacity of defendants to ensure that they can fully understand the course of criminal proceedings.

Who are Vulnerable Individuals?

Individuals who are unable to:

  • To comprehend the course of proceedings of the trials, so as to make a proper defence.
  • To know that they might challenge any jurors to whom they may object.
  • To comprehend the evidence.
  • To give proper instructions to their legal representatives.
  • To decide whether to plead ‘guilty’ or ‘not guilty’.


Historically, whilst early legal systems traditionally provided partial leniency towards individuals displaying mental or physical difficulties, a plethora of research has documented the vast and harrowing accounts of maltreatment towards such individuals. Specifically, the absence of a fair or just trial within the criminal justice system, and the disproportionate numbers of unjust incarcerations. Redlich, Kulish & Steadman (2011) stipulated that mental impairment is a commonly recognised risk factor for false confessions. Additionally, Redlich et al., (2010) interviewed 1,249 offenders with mental health issues and 22% self-reported inaccurately confessing to an offence, as a result of failing to understand the evidence accurately.

Today, the standardised test of legal fitness in England and Wales is based on the influential ruling of Alderson. B in R v Pritchard in 1836. This prominent case represented one of the fundamental catalysts that revolutionised the understanding of mental capacity within a legal context. To date, it remains one of the most pivotal legal benchmarks to dictate a defendant’s state of mind. The case involved a deaf and mute defendant who was determined unfit to plead by a judge, due to low intellect and severe communication and cognitive deficits. Following the ruling that the defendant lacked the mental capacity to plead, three essential requirements were introduced to enhance the protection of individuals in court, and to determine a defendant’s capacity:

1) To decide whether the defendant is mute of malice or not
2) To decide whether they can plead to the indictment or not
3) To decide whether they are of sufficient intellect to comprehend the course of the court proceedings in the trial, so as to make a proper defence.

Following the landmark progression, the perception and understanding of psychiatry significantly advanced throughout the 20th century, resulting in the improvement of diagnostic criteria surrounding fitness to plead in court, and advancing the understanding and treatment of mental disorders more generally. In particular, the Criminal Law Committee proposed a series of recommendations, after reviewing the fitness to plead criteria. These recommendations were swiftly implemented by the Criminal Procedure Insanity Act (CP(I)A) in 1964, which stipulated that the prosecution and jury must prove beyond reasonable doubt that the defendant may be declared as fit to plead. Over subsequent decades, the Act was replaced with the Criminal Procedure (Insanity and Unfitness to Plead) Act in 1991.

This Act provides a more comprehensive and multi-faceted understanding of mental capacity within a legal context, by using a ‘Trial of Fact’ to enable the jury the ability to determine their satisfaction regarding the defendant’s fitness to plead. The Act also implemented the notion of acquittals on the grounds of insanity, and greater powers to deal with the defendant’s not guilty by reason of insanity or unfit to plead.


The passing of the Human Rights Act in 1998 marked the introduction of the framework incorporating fitness to plead, and the safeguarding of individual’s rights became integrated into English Law for the first time. Articles 5 and 6 of the Act demonstrate the intrinsic purpose to protect the right to a fair trial, and to liberty.

Overall, whilst our understanding of mental disorders in a legal context has hugely evolved and improved over time, the fitness to plead principle has been prevalent for centuries. Development in understanding and treating mental disorders, coupled with the proliferation of human rights legislation in recent decades, has significantly improved the protection of vulnerable individuals in court.

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