The Supreme Court has dismissed an appeal by John Cash over the use of fingerprint records to support his arrest on suspicion of burglary, ruling that prosecutors did not have to prove the records’ lawful provenance to establish reasonable cause for arrest.
The judgment, delivered by Mr Justice Fennelly on 18 January 2010, concerned a case stated from the District Court. Cash was charged with entering a building on Kylemore Road, Clondalkin, on 21 July 2003, as a trespasser with intent to commit theft. The appeal arose after the prosecution had presented its evidence and the District Court judge indicated she was minded to admit it and find that Cash had a case to answer. The case stated sought the High Court’s advice on whether that decision was correct.
The evidence involved three sets of fingerprints. Gardaí found prints on broken window glass at the property. A fingerprint expert said those prints matched a set held in Garda records, dated 31 March 2002 and bearing Cash’s name. The detective who arrested Cash said the match was the sole basis for his suspicion. Garda witnesses could not say whether the earlier records had been lawfully taken or retained. The judgment noted that, if obtained under statutory powers, prints could be subject to a six-month destruction requirement in certain circumstances; there was no evidence about how this set had been obtained.
Cash argued that the rule excluding evidence obtained through breaches of constitutional rights should extend to material used to form the suspicion behind an arrest, even if that material was not itself offered at trial. The Court rejected that proposed extension. It held that the rules governing admissibility of trial evidence do not require prosecutors to prove the lawful origin of every item of information that may have contributed to reasonable cause for arrest. The judgment stressed that an arrest must still have reasonable cause and be made for an authorised purpose.
A separate issue concerned fingerprints taken from Cash in detention with his written consent. The judgment said that point was no longer in issue on appeal, following the Court’s earlier decision in DPP v Boyce. Whether Cash had in fact consented remained for the District Court judge to determine after hearing the evidence.
The Supreme Court dismissed the appeal and affirmed the High Court order. It did not decide whether the disputed fingerprints were lawfully obtained, whether Cash actually consented to the later prints, or whether he was guilty. The underlying charge remained for determination in the District Court.