A "priceless blunder" by a major Cork drug dealer and career criminal led him to sabotage his own appeal over the severity of a sentence he received for possession of almost 5,000 ecstasy tablets.

John Heaphy (58), from Fairhill in Cork, was caught with a large coffee jar of ecstasy tablets in his hands after a three-day stakeout in an unkempt field in Rathpeacon, Co Cork, in 2007. In 2008, he was jailed for 12 years, with the last five years of the sentence suspended.

During his trial, gardaí told the court that each of the 4,735 pills would sell for €10, so the worth of the haul was approximately €47,000. Under section 15(A) of the Misuse of Drugs Act 1977, anyone caught in possession of drugs worth €13,000 or more attracts a minimum 10-year sentence. But the career criminal appealed the severity of his conviction on Monday, claiming that the actual street value of each tablet was between €1 and €3, meaning the haul was worth less than €13,000 and should not have attracted the mandatory minimum sentence.

However, at the Court of Criminal Appeal on Monday, gardaí were able to produce transcripts of what he told detectives during interviews in custody. Heaphy told gardaí he could "get a fiver" for each pill. This would mean that the pills were worth over €23,000 and therefore, by his own admission, attracted the mandatory minimum sentence of at least 10 years. His appeal was therefore immediately dismissed.