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District Court 7 May 2025

Karlsson v R

[2025] NSWDC 173

Public order & justice offences
CRIME EVIDENCE LIMITATION ON “BUT FOR” TEST

Citation: Karlsson v R [2025] NSWDC 173
Court: District Court of NSW
Date: 7 May 2025
Judge: Newlinds SC DCJ

Background

The appellant was stopped by police at Potts Point in October 2023 after voluntarily admitting he had no valid public transport ticket. A police constable identified him, ran a criminal history check, and then questioned him about whether he was carrying drugs. The appellant made what the constable reasonably interpreted as an admission to possessing illicit drugs (the drugs were later found to be legal). The constable then attempted to search him.

The appellant resisted the search and used offensive language during that interaction. He was convicted in the Local Court of hindering police and using offensive language in a public place. He appealed to the District Court on the ground that all the relevant evidence should have been excluded under section 138 of the Evidence Act 1995 (NSW).

The Local Court Magistrate had found no illegality or impropriety in the constable's conduct and therefore did not engage the section 138 discretion at all.

Legal Issues

  • Whether the constable's detention of the appellant and questioning him about drug possession was unlawful under section 21 of the Law Enforcement (Powers and Responsibilities) Act 2002 (NSW) (LEPRA).
  • Whether the failure to caution the appellant before questioning him about drugs amounted to impropriety for the purposes of section 138 of the Evidence Act.
  • Whether evidence of the appellant's subsequent resistance and offensive language was "obtained in consequence of" the identified impropriety or illegality, so as to engage the section 138 discretion.
  • How the causation requirement in section 138 should be construed, and in particular whether a pure "but for" test applies or whether some objective foreseeability limit constrains it.
  • Whether, if the discretion was engaged, the evidence should be excluded.

Decision

Issue 1: Was the detention and questioning unlawful?

The constable accepted in cross-examination that the appellant was not free to leave during the questioning about drugs, and that it was only upon receiving the admission that he considered he had reasonable grounds for suspicion under section 21 of LEPRA (at [15]). Without that admission, the only factors available were the appellant's unkempt appearance, the King's Cross location, and a criminal history, which the court found would not together constitute reasonable grounds (at [14]). Because the admission was itself obtained during an unlawful detention, the constable's suspicion was not founded on "reasonable grounds" as required by section 21 of LEPRA, rendering the detention a false imprisonment (at [16]). The failure to caution the appellant before questioning him about drugs, while not necessarily a breach of statute, was found to be an impropriety within the meaning of section 138 because it breached safeguards under Part 9 of LEPRA and section 139 of the Evidence Act (at [19]).

Issue 2: Is section 138 engaged by evidence of the appellant's subsequent conduct?

This was the central legal question. The evidence sought to be excluded was not a direct product of the unlawful detention, but rather the appellant's reaction (resistance and offensive language) to a search that followed from it. The court considered whether that reaction was "obtained in consequence of" the impropriety under section 138 (at [23]-[27]).

After surveying the authorities, including Smart AJ in DPP v Carr (2002), Adams J in DPP v Coe (2003), and Hall J in DPP v AM (2006), the court concluded that a pure "but for" test without any limiting principle would produce absurd outcomes and would render the gateway to the discretion effectively otiose (at [43]). The better construction, drawing on Hall J's reasoning in AM and Bell J's acceptance of it in DPP v Kaba (2014), is that evidence will be "in consequence of" an impropriety only if the subsequent conduct was objectively expected or anticipated to arise from the impugned police conduct (at [44]-[45]).

Applying that test, the court was satisfied that a person being subjected to a body search following unlawful detention might objectively be expected to resist and use offensive language. The gateway to the section 138 discretion was therefore open (at [49]).

Issue 3: Exercise of the discretion

The court then exercised the discretion afresh. On one side, the evidence was essential to the Crown's case and therefore highly probative (at [54]). On the other, the impropriety was at the lowest end of the scale, the constable acted in good faith and honestly believed his conduct was lawful, and the offences themselves were minor, with the language used described as borderline offensive in contemporary terms (at [51]-[52]). Balancing those factors, the court concluded the evidence should have been excluded (at [54]).

Orders Made

  • Appeal allowed.
  • The Magistrate's orders of 9 August 2024 relating to the two charges set aside.
  • Sequence 1 (hindering police in the execution of duty, contrary to section 61AA Crimes Act 1900 (NSW)): not guilty.
  • Sequence 6 (using offensive language in a public place, contrary to section 4A Summary Offences Act 1988 (NSW)): not guilty.

Key Takeaways

  • A pure "but for" causation test under section 138 of the Evidence Act is insufficient on its own. The District Court held, following Hall J in DPP v AM and Bell J in DPP v Kaba, that an outer limiting principle applies: evidence of subsequent conduct is only "obtained in consequence of" an impropriety if that conduct was objectively expected or anticipated to result from the impugned police action (at [43]-[45]).

  • Unlawful detention under section 21 of LEPRA cannot be bootstrapped by suspicion that was itself generated during the unlawful detention. Where a constable's reasonable grounds depend entirely on an admission obtained while a person was already unlawfully detained, those grounds do not satisfy the statutory threshold (at [15]-[16]).

  • Failure to caution a suspect before questioning them about a possible offence unrelated to the original investigation can constitute an impropriety for section 138 purposes, even if it does not breach a specific statutory prohibition (at [19]).

  • The section 138 discretion may favour exclusion even where police acted in good faith, if the offences charged are minor and the impropriety, though unintentional, contributed causally to the evidence obtained (at [51]-[54]).

  • Evidence of a suspect's resistance to and offensive language during an unlawful search can fall within the section 138 gateway when resistance to such a search is an objectively foreseeable response, even though that evidence arises from the suspect's own subsequent conduct rather than directly from the unlawful police action (at [47]-[49]).

Legislation and Cases Referenced

Legislation
- Crimes Act 1900 (NSW) s 61AA
- Crimes ( Appeal and Review) Act 2001 (NSW) s 18
- Evidence Act 1995 (NSW) s 138
- Law Enforcement ( Powers and Responsibilities) Act 2002 (NSW) s 21
- Summary Offences Act 1988 (NSW) s 4A

Cases
- Charara v The Queen [2006] NSWCCA 244
- DPP v AM (2006) 161 A Crim R 219
- DPP v Carr (2002) 127 A Crim R 151
- DPP v Coe [2003] NSWSC 363
- DPP v Kaba (2014) 44 VR 526
- Lunney v Director of Public Prosecutions [2021] NSWCA 186
- R (Cth) v Petroulias (No. 8) [2007] NSWSC 82
- R v Cornwall [2003] NSWSC 97
- R v Dalley (2002) 132 A Crim R 169
- R v Haddad (2000) 116 A Crim A 312
- Reyes-Carrion v The State of New South Wales [2025] NSWDC 28
- Ridgeway v R (1995) 184 CLR 19