The origins of the concept of fitness to plead in English law lie in the traditional roots of medieval court procedures. However, the foundation on which the criteria rely on appears to frustrate the reforms which are designed to make the process and consequences of being unfit to plead more reasonable. Unfitness to plead is designed to protect those defendants whose mental or physical conditions prevent them from being able to participate and engage effectively in the criminal trial process.
The legal test for unfitness has been embedded in the common law and has not been considered again since the Butler Report in 1975, which recommended reform. However, the same cannot be said for the procedural changes. They have been implemented on the following occasions:
Unfitness to plead is designed to protect those defendants whose mental or physical conditions prevent them from being able to participate and engage effectively in the criminal trial process.
1. The Criminal Procedure (Insanity) Act 1964 made a series of such changes to unfitness to plead.
2. The Criminal Procedure (Insanity or Unfitness to Plead) Act 1991 introduced the trial of facts (Section 4A) and flexibility of disposal for both unfitness and insanity (excepting murder charges).
3. The Domestic Violence, Crime and Victims Act 2004 removed the role of the jury for findings of unfitness, reduced the range of disposals to three by removing a guardianship order as a disposal option and ensured that if a hospital based disposal was made it must comply with the requirements of the Mental Health Act 2007.
All these changes have constituted important progress in the law surrounding unfitness to plead. However, it appears that the crucial matter which desperately needs further re-examination has been put to the side: a new legal test must be implemented so that potentially unfit defendants will not have to unfairly continue to face the severity of a full criminal trial.
Clarification: insanity and unfit to plead
It is often confusing to distinguish between insanity and unfitness to plead. The two concepts differ in that unfitness to plead is concerned with the question of an accused’s mental state at the time of the trial and not at the time of the offence.
…the Law Commission proposed a new legal test based exclusively on decision-making capacity.
The Pritchard case and its outcome
For an accused to be unfit to plead under the present law there must be a finding that an accused is under a disability that would constitute a bar to a trial. However, the criteria to determine an individual’s unfitness to plead have never been the subject of legislation. The underlying principle was established in R v Dyson (1831) 7 C & P. 305, but was more fully illustrated in R v Pritchard (1836) 7 C & P. 303 by Baron Alderson.
As noted by Don Grubin, the case of Dyson raised the following precedents: (a) it brought idiocy under the umbrella of insanity by establishing that those found unfit to plead were ‘not sane’ and (b) it established intelligence as the foundation on which future decisions about fitness to plead were to be made. Subsequently, in the case of Pritchard, Baron Alderson directed the jury that to be fit to plead the accused must be:
[O]f sufficient intellect to comprehend the course of proceedings in the trial so as to make a proper defence, to know that he may challenge any of you to who whom he may object and to comprehend the details of the evidence.
Having also given the approval of the Pritchard criteria in the case of R v M (2003) EWCA Crim 3452, the Court of Appeal stated:
[T]hose authorities clearly establish the law on this topic in this jurisdiction. When we consider the judge’s directions in the present case in the light of those authorities we can find no deficiency in them. Indeed, this Court regards them as admirable directions. They do not set the test of fitness to plead at too low a level.
On the other hand, the Law Commission has been critical of this approach and has expressed the following:
[W]e think that an analysis of the case law, shows that, at best, the criteria are not comprehensive and place a disproportionate emphasis on low intellectual ability. At worst the criteria simply set too high a threshold for finding an accused to be unfit to plead and are inconsistent with the modern trial process.
The Pritchard criteria have found legitimate ground in their long history.
In return, the Law Commission proposed a new legal test based exclusively on decision-making capacity. They believed that the foremost problem of the Pritchard criteria was its focus on cognitive ability, which resulted in a failure to take mental capacity and participation into account as part of the legal test. When developing this new test, the Law Commission relied on Section 3 of the Mental Capacity Act 2005 and in doing so it considered that such a test will certify that the compulsory requirements for involvement are met:
[W]e provisionally propose that an accused should be found to lack capacity if he or she is unable:
(1) to understand the information relevant to the decisions that he or she will have to make in the course of his or her trial
(2) to retain that information
(3) to use or weigh that information as part of decision making process, or
(4) to communicate his or her decisions.
However, should this new legal test be based exclusively on decision-making capacity at the expense of any precise reference to an accused’s cognitive abilities? It is also interesting that the Law Commision proposes that:
A defined psychiatric test to assess decision-making capacity should be developed and this should accompany the legal test as to decision-making capacity.
This might imply that the psychiatric instrument will have the force of law and if it is indeed the case, the statute will be expected to undergo frequent changes in order to satisfy the requirements of the continuous psychiatric research.
What Professor Mackay demonstrates is for the introduction of ‘decisional competence’ into any reworked test of unfitness to plead but not abandoning the Pritchard criteria but rather by clarifying and supplementing them with a new limb.
A good example of how ‘decisional competence’ operates as a new limb is portrayed in the case of Attorney General v O’Driscoll  JLR 390, where the Royal Court of Jersey refused to apply the Pritchard criteria and instead introduced a new test for unfitness to plead which follows:
[A]n accused person is so insane as to be unfit to plead to the accusation, or unable to understand the nature of the trial if, as a result of unsoundness of mind or inability to communicate, he or she lacks the capacity to participate effectively in the proceedings.
In determining this issue, the Superior Number shall have regard to the ability of the accused:
(a) to understand the nature of the proceedings so as to instruct his lawyer and to make a proper defence;
(b) to understand the substance of the evidence;
(c) to give evidence on his own behalf;
(d) to make rational decisions in relation to his participation in the proceedings, (including whether or not to plead guilty), which reflect true and informed choices on his part.
It is apparent that this declaration maintains the foundations of the benchmark case of Pritchard and essentially clarifies and updates its criteria. In the words of Mackay: the ruling in O’Driscoll acts as a catalyst for reform and it is important in itself as it adopts a test for unfitness to plead which is not restricted to an ability to understand the trial process. Instead, it supports the notion of the need for ‘decisional competence’ before a defendant who is of unsound mind or unable to communicate, can be adjudged to have ‘the capacity to participate effectively in the proceedings’.
What reforms should be made on the Pritchard criteria?
The Pritchard criteria have found legitimate ground in their long history. Due to the fact that they have been established since the 1800s and their concept is part of the common law, their applicability to modern legal and psychiatric practice is seldom disputed. What must be highlighted is that if a defendant is unable to engage properly in the trial then the defendant cannot be suitably or justly tried.
According to Professor Duff:
[T]his is not just because the verdict might then be unsafe, but because it is a travesty of justice to call someone who cannot answer, or to hold responsible and condemn someone who cannot understand or respond to that condemnation . 
Ultimately, what needs to be done? On the one hand, there is the suggestion of maintaining the Pritchard criteria and accompanying this with the concept of decisional competence until the right criteria is eventually formulated. However, that could take many years. On the other hand, a rather drastic resolution would be to completely abandon the criteria and overturn more than 150 years of legal tradition.
 R.D Mackay, “ Uniftness to plead – some observations of the Law Commission’s Consultation Paper” (2011) 6 Crim. L.R 433
 Don Grubin, “What constitutes fitness to plead?” (1993) Crim. L.R 748, at pg 753
 R v Pritchard (1836) 7 C & P 303, at page 304
 R v M (2003) EWCA Crim 3452, at 
 Law Commission, Unfitness to Plead (Law Com, Consultation Paper CP No.197, 2010)
 Ibid, at para 3.13
 Ibid, at para 5.17
 Mackay (n1), at page 435
 Attorney General v O’Driscoll (2003) JLR 390 (Royal Court of Jersey)
 R.D Mackay, ‘On being insane in Jersey: Part 3 – The case of Attorney General v O’Driscoll’ (2004) Crim L.R 291, at page 296
 R.A Duff, ‘Fitness to plead and fair trial: Part 1: A Challenge’ (1994) Crim L.R 419, at page 421