Jamie Watson was due to stand trial after he was allegedly found dealing cocaine to another man in Douglas on January 23 last year.
Watson denied the offence although he did plead guilty to possessing the class A drug at the lower courts.
The 25-year-old was due to stand trial on Monday (January 13) but Deemster Cook dismissed the case at General Gaol Delivery on Friday.
Peter Connick, prosecuting, formerly asked for the case to be dismissed after telling the court police had sent off the wrong wrap of alleged cocaine for analysis.
One wrap was thought to contain 0.3g of cocaine but the other only had trace amounts.
Mr Connick explained the wrap containing trace amounts had been sent for analysis in error. Not only that, but he explained police had received the results of the analysis on July 16, 2024 but the Attorney General’s Chambers was only told the of the results on January 6 this year.
Deemster Cook said: ‘How the police have dealt with this is beyond belief. This is appalling.’
He also criticized the Attorney General’s Chambers for allowing the case to get to this stage.
He told Mr Connick: ‘You should not have allowed this case to go beyond committal without getting the analysis results. The jury have been sworn in. There have been wasted costs.’
In relation to possessing cocaine, Watson was fined £10 and was allowed to leave the court.
Afterwards, a spokesperson for Isle of Man Constabulary said: ‘We are aware of Deemster Cook’s remarks in court and an internal review will take place to establish the circumstances.’