A Timaru man who pranked a woman by having pizzas delivered and a taxi sent to her door has had his conviction overturned because the police "trick" used to track him down was illegal.
Richard Arthur James Crawford on more than one occasion ordered the pizzas and once had a taxi sent to take the woman to hospital.
However, she was able to get the cellphone number from which the order was made and gave it to police.
A police sergeant called the number, with no reply, but sent a text, saying the person was the winner of two movie passes and a name and address was needed to send them out.
Mr Crawford immediately replied and a few days later the sergeant knocked on his door.
He initially denied making the pizza orders, Justice Nick Davidson said in his High Court judgement delivered on Thursday.
"Then the sergeant said he was 'the Movie Max guy', whereupon the appellant slapped his head, said 'I'm so dumb', accompanied the sergeant to the station, and made a full confession."
However, Justice Davidson said while Mr Crawford was charged and convicted in the Timaru District Court - it is not clear what the charge was - the evidence was improperly obtained and the sergeant had committed an offence by "using a telecommunications device knowingly giving a false message".
Although Mr Crawford had slapped his head and said "I'm so dumb", Justice Davidson said "there were other investigatory techniques available, there was no urgency, and the impropriety, 'the trick', was not necessary to avoid any loss of evidence".
Although there was a "sinister element" to Mr Crawford's actions, the judge decided the police officer's conduct was well intentioned but he needed to reflect on whether the line which marks impropriety would be crossed.