John McGinty

John McGinty was found guilty of supplying a controlled drug in contravention of the Misuse of Drugs Act 1971. Evidence was introduced at trial to show traces of cannabis on banknotes in his possession. On appeal, this evidence was found to be of little significance because scientific evidence has shown such reports are open to serious challenge. Specifically, research from a specialist laboratory showed that a large number of bank notes acquired traces of drugs in the course of circulation. For the finding of traces of cannabis on banknotes to have any evidential significance, it had to be demonstrated that the frequency and levels of contamination differed significantly from those found on banknotes taken from general circulation. The Crown evidence had not referred to the possibility that traces were acquired in general circulation. The court noted that a verdict returned in ignorance of this relevant research must be regarded as a miscarriage of justice, and quashed the conviction.