Arulthilakan v The Queen, Mkoka v The Queen

The High Court of Australia considered appeals by Arulthilakan and Mkoka against their convictions for murder. Both appellants had been convicted in separate trials in the Supreme Court of New South Wales. The central issue on appeal concerned the admissibility of evidence obtained through the use of a listening device, specifically whether the evidence was obtained unlawfully and, if so, what the consequences of that unlawliness were for its admission at trial.

The primary legal question before the High Court was whether the evidence obtained by the police using a listening device, pursuant to a warrant issued under the *Listening Devices Act 1984* (NSW), was unlawfully obtained. This question hinged on whether the warrant was validly issued, given that the police had not disclosed to the issuing officer the fact that they had already placed a listening device in the relevant premises prior to seeking the warrant. The court was required to determine the proper interpretation of the *Listening Devices Act 1984* (NSW) and the implications of any unlawful conduct by the police on the admissibility of the evidence under section 138 of the *Evidence Act 1995* (NSW).

The High Court held that the evidence obtained by the listening device was unlawfully obtained. The court reasoned that the police had a duty to disclose all relevant information to the issuing officer, including the fact that the device had already been installed. Failure to do so meant the warrant was not validly issued, rendering the subsequent use of the device unlawful. Applying section 138 of the *Evidence Act 1995* (NSW), the court found that the unfairness to the accused in admitting the unlawfully obtained evidence outweighed the public interest in ensuring that criminal convictions were secured. Consequently, the convictions were quashed, and the court ordered that the appellants be discharged.