Thomas v State of New South Wales

The case of *Thomas v State of New South Wales* concerned an appeal to the Court of Appeal of New South Wales. The appellant, Thomas, brought an action against the State of New South Wales for malicious prosecution. The central issue arose from evidence given by an investigating police officer to a Police Royal Commission, which indicated that the officer's testimony regarding admissions of guilt made by the appellant had been fabricated.

The Court of Appeal was required to determine, in the context of a malicious prosecution claim, the nature of the subjective belief a prosecutor must hold concerning the case they are prosecuting. Specifically, the court had to consider whether there was a reasonable basis for the prosecutor's belief and whether the material capable of forming such a reasonable basis was limited to that which would be admissible in evidence.

The court reasoned that the prosecutor's belief must be based on reasonable grounds, and that the evidence available to the prosecutor at the time of the decision to prosecute was the relevant material. The fabricated evidence provided by the police officer to the Royal Commission, while demonstrating the unreliability of the prosecution's case, did not retroactively invalidate the prosecutor's belief at the time the decision was made, provided that belief was reasonably held based on the information then available. The court applied established principles of malicious prosecution, focusing on the prosecutor's state of mind and the objective reasonableness of their assessment of the evidence.

The appeal was dismissed, and the appellant was ordered to pay the costs of the proceedings.