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Court of Criminal Appeal 13 June 2025

Delaney v R

[2025] NSWCCA 76

Homicide
CRIME APPEALS APPEAL AGAINST CONVICTION MISCARRIAGE OF JUSTICE

Citation: Delaney v R [2025] NSWCCA 76
Court: NSW Court of Criminal Appeal
Date: 13 June 2025
Judges: Harrison CJ at CL, Davies J (principal judgment), Weinstein J

Background

The applicant pleaded guilty in April 2022 to the murder of his sister, committed on 3 June 2020. He was subsequently sentenced in the Supreme Court to 21 years' imprisonment with a non-parole period of 15 years and 9 months. The applicant had been under the influence of drugs at the time of the offending and had been diagnosed with schizophrenia.

Before entering his plea, the applicant's lawyers obtained forensic psychiatric reports from two experts. Both diagnosed the applicant with schizophrenia but concluded that a defence of mental health impairment was unavailable, on the basis that acute drug intoxication could not be excluded as "the most important factor" in the offending. Relying on that expert opinion, the applicant's lawyers advised him that drug use would need to be entirely excluded before he could rely on the defence. The applicant entered his guilty plea on the basis of that advice.

The applicant later sought leave to appeal against both his conviction and his sentence. He contended that the expert evidence and legal advice he received rested on a misunderstanding of the statutory definition of "mental health impairment" under the Mental Health and Cognitive Impairment Forensic Provisions Act 2020 (NSW) (the MHCIFP Act). Because the conviction appeal succeeded, the Court did not need to address the sentence appeal.

  • Whether the advice given to the applicant about the unavailability of the mental health impairment defence was wrong, and whether that error constituted a miscarriage of justice.
  • Whether the correct test under s 4(3) of the MHCIFP Act is a "caused solely by" test (as the provision states) rather than a broader "but for" or "most important factor" test.
  • Whether, where the Crown asserts that an accused's impairment is excluded by s 4(3) (on the basis that it was caused solely by drug ingestion or substance use disorder), the Crown bears the onus of proving that exception.

Decision

The statutory test under s 4(3)

Section 4(1) of the MHCIFP Act defines "mental health impairment." Section 4(3) carves out an exclusion: a person does not have a mental health impairment for the purposes of the Act if the impairment is "caused solely by" the ingestion of a substance or a substance use disorder. Davies J held that this language cannot be equated with a "but for" test or a "most important factor" test. It requires that the impairment be caused solely, and only, by drug ingestion.

The advice was wrong

Both experts diagnosed the applicant with schizophrenia and both concluded that schizophrenia and drug ingestion were each factors in the offending. Critically, neither expert stated that the mental health impairment at the time of the offending was caused solely by drug ingestion. Despite that, both experts advised that the defence was unavailable, and the applicant's lawyers adopted that position in advising him to plead guilty. Because the expert opinions and the resulting legal advice applied the wrong legal test, the advice was wrong. The applicant was deprived of the chance of a special verdict, and a miscarriage of justice occurred.

Onus of proof under s 4(3)

The Court held that s 4(3) operates as an exception or qualification to s 4(1). Where the Crown seeks to rely on s 4(3) to negate an accused's claim to a mental health impairment, the onus of establishing that exception rests on the Crown. There is no onus on the accused under s 4(3), even where the accused's own evidence raises substance use as a factor. Unless it is proved that the impairment was caused solely by the substance or substance use disorder, the accused is not precluded from relying on a mental health impairment. The Court endorsed the approach taken by Cavanagh J in R v Miller and the directions given by Dhanji J in R v Patterson (No 6) as the preferred approach in such cases.

Orders Made

  • Time for filing the Notice of Appeal extended to 28 November 2024.
  • Leave to appeal granted.
  • Appeal upheld.
  • Conviction quashed.
  • Leave granted to the applicant to withdraw his guilty plea to the murder of Gabriella Delaney.
  • Matter remitted to the Supreme Court for retrial.
  • Matter stood into the Arraignments List in the Supreme Court on 4 July 2025.

Key Takeaways

  • The "caused solely by" test in s 4(3) of the MHCIFP Act has a precise and narrow meaning. It is not satisfied merely because drug intoxication was an important or contributing factor in the offending; the impairment must have been caused by nothing other than the substance ingestion or substance use disorder.
  • Where an accused relies on a mental health impairment defence and the Crown contends that s 4(3) applies, the Court of Criminal Appeal confirmed that the Crown bears the onus of proving the s 4(3) exclusion. This follows from s 4(3) operating as an exception to s 4(1).
  • A guilty plea entered on the basis of incorrect legal advice about the availability of a statutory defence can constitute a miscarriage of justice under s 6 of the Criminal Appeal Act 1912 (NSW), sufficient to warrant setting aside the conviction.
  • Expert psychiatric evidence that does not engage with the specific statutory test, even when prepared by qualified forensic psychiatrists, may be insufficient to properly advise on the availability of a mental health impairment defence.
  • Directions consistent with R v Patterson (No 6) [2024] NSWSC 458 were endorsed as the preferred approach where an accused relies on mental health impairment and the Crown invokes s 4(3).

Legislation and Cases Referenced

Legislation
- Mental Health and Cognitive Impairment Forensic Provisions Act 2020 (NSW), ss 4, 14, 28, 36
- Crimes Act 1900 (NSW), s 23A
- Criminal Appeal Act 1912 (NSW), s 6

Cases
- Fang v R (2018) 97 NSWLR 876; [2018] NSWCCA 210
- R v De Souza (1997) 41 NSWLR 656
- R v Murray [2024] NSWSC 503
- R v Patterson (No 6) [2024] NSWSC 458
- TKWJ v The Queen (2002) 212 CLR 124; [2002] HCA 46
- R v Falconer (1990) 171 CLR 30; [1990] HCA 49
- Dowling v Bowie (1952) 86 CLR 136
- R v Miller [2022] NSWSC 802
- R v Jawid [2022] NSWSC 788
- R v Sheridan [2022] NSWSC 1669
- R v Delaney [2022] NSWSC 1327
- Waters and Others v Mercedes Holdings Pty Ltd and Others [2012] FCAFC 80; (2012) 289 ALR 489
- White v R (2022) 110 NSWLR 163; [2022] NSWCCA 241
- RE v R [2024] NSWCCA 180
- Layt v R [2020] NSWCCA 231
- Xie v R [2021] NSWCCA 1; (2021) 386 ALR 371
- Sagiv v R (1986) 22 A Crim R 73
- R v Radford (1985) 42 SASR 266