Maintaining Conviction Integrity: The Court of Appeal's Stance on Admitting Retrospectively Revised Psychiatric Evidence - Hunnisett v Crown

Introduction

Hunnisett, R. v ([2021] EWCA Crim 265) is a pivotal case adjudicated by the England and Wales Court of Appeal (Criminal Division) on March 4, 2021. The appellant, identified herein with female pronouns due to her self-identification as female over the past five years, was convicted of the murder of Peter Bick. Initially sentenced to life imprisonment with a minimum term of 18 years, her conviction was later referred to the Court of Appeal by the Criminal Cases Review Commission (CCRC) based on newly surfaced psychiatric evidence. This commentary delves into the background of the case, the Court's judgment, and its broader implications on the legal landscape concerning the admission of fresh psychiatric evidence in criminal appeals.

Summary of the Judgment

The appellant's conviction for the murder of Peter Bick was initially upheld in 2012, where defenses of diminished responsibility and loss of control were presented but ultimately rejected by the jury. The CCRC later referred the case to the Court of Appeal, citing a revised psychiatric opinion from Professor Jennifer Shaw, who had originally testified against the defense. In her new assessment, Professor Shaw posited that the appellant suffered from a psychotic illness at the time of the crime, thereby making diminished responsibility applicable and potentially altering the conviction from murder to manslaughter.

However, the Court of Appeal denied the admission of this fresh evidence, thereby dismissing the appeal. The core reasoning hinged on the appellant's history of unreliable narratives, the inconsistency of the new psychiatric diagnosis with the longstanding expert opinions from the original trial, and the evolution of her mental health condition post-conviction, which was deemed irrelevant to the original charge.

Analysis

Precedents Cited

The judgment extensively references key legal precedents that shape the Court of Appeal's handling of fresh evidence:

• Pendleton [2001] UKHL 66; Lord Bingham emphasized that courts should avoid delving into jury deliberations and maintain respect for the original trial's integrity.
• R v Criminal Cases Review Commission, ex parte Pearson [1999] highlighted the discretionary power of the Court of Appeal to admit fresh evidence, stressing the criteria outlined in section 23 of the Criminal Appeal Act 1968.
• Kai Whitewind [2005] EWCA Crim 1092; underscored the rarity of admitting repeated or similar expert evidence post-trial, especially when initial expert testimonies were not persuasive to the jury.

These precedents collectively reinforce the Court's cautious approach towards reopening cases based on new psychiatric evaluations, particularly when such evidence does not substantially diverge from the original assessments or when the appellant's credibility is questionable.

Legal Reasoning

The Court's legal reasoning in this case centered on multiple interconnected factors:

• Credibility of the Appellant: The appellant's history of providing inconsistent accounts and her tendency to fabricate narratives significantly undermined the reliability of the new psychiatric evidence.
• Consistency of Expert Opinions: A substantial body of expert testimony over the years consistently negated the presence of a psychotic disorder, rendering Professor Shaw's revised opinion anomalous within the context of established psychiatric evaluations.
• Relevance of Subsequent Mental Health Developments: The appellant's deteriorating mental health post-trial, including diagnoses and self-harm incidents, was deemed irrelevant to her mental state at the time of the crime, thus not constituting fresh evidence pertinent to her original conviction.
• Impact on Judicial Integrity: Admitting such retrospective psychiatric evidence could potentially erode the trust in jury verdicts and the overall judicial process by allowing post hoc reconsiderations based on fluctuating mental health assessments.

The Court concluded that admitting Professor Shaw's new evidence would not sufficiently demonstrate that the original conviction was unsafe. The fresh evidence was either a reiteration of previously considered factors or originated from developments irrelevant to the appellant's mental state during the original offense.

Impact

The judgment in Hunnisett v Crown has significant implications for future criminal appeals, particularly regarding the admission of psychiatric evidence:

• Reaffirmation of High Thresholds: The decision reinforces the necessity for fresh evidence to be not only credible and substantially different from existing evidence but also directly relevant to the circumstances of the original conviction.
• Protection of Jury Verdicts: It emphasizes the importance of maintaining the sanctity of jury decisions, discouraging appeals based on retrospective or evolving psychiatric assessments unless incontrovertibly impacting the safety of the conviction.
• Guidance on Expert Testimony: The judgment provides a clear guideline that expert witnesses revising their opinions post-trial, especially those previously involved in the case, must present compelling and substantial deviations from prior assessments to influence appellate outcomes.
• Appellant's Credibility Scrutiny: Future appeals will likely see heightened scrutiny of the appellant's credibility, especially in cases where new evidence relies heavily on the appellant's narratives or disclosures.

Overall, the case serves as a cautionary exemplar for both appellants and legal practitioners, delineating the rigorous standards governing the admission of fresh evidence and the pivotal role of consistent, reliable expert testimony in safeguarding judicial integrity.

Complex Concepts Simplified

Understanding the intricacies of this judgment requires unpacking several complex legal and psychiatric concepts:

• Fresh Evidence: This refers to new information that was not available or presented during the original trial, which could potentially influence the outcome of the case if considered by the appellate court.
• Diminished Responsibility: A partial defense to murder in English law, where the defendant can be found guilty of manslaughter instead if they can prove that their mental faculties were significantly impaired at the time of the crime.
• Psychotic Illness: A severe mental disorder characterized by a disconnection from reality, which can include symptoms like delusions and hallucinations, potentially impairing an individual's ability to make rational decisions.
• Section 23 of the Criminal Appeal Act 1968: Provides the legal framework for appellate courts to admit new evidence in criminal appeals, outlining specific criteria that must be met for such evidence to be considered.
• CCRC (Criminal Cases Review Commission): An independent public body that investigates possible miscarriages of justice in criminal cases, with the authority to refer cases back to higher courts for reconsideration.

By simplifying these concepts, one can better appreciate the legal thresholds and psychiatric evaluations that underpin the Court of Appeal's decision in this case.

Conclusion