A security expert at the Kofi Annan Peacekeeping Training Centre has attributed the acquittal of two drug barons by the Appeals Court to weaknesses in state investigation and prosecution.Dr. Kwasi Annin says some of the investigators “need to go back to school,” for retraining.Alhaji Abass and Kwabena Amaning, alias Tagor, were released Saturday after spending 19 months of their 15-year term imposed by a High Court for drug related offences.The Appeals Court quashed that decision for lack of evidence and ordered their immediate release.In an interview with Joy News’ Matilda Asante on Monday, Dr. Annin expressed surprise over why the investigative team tendered in as evidence a taped conversation of the drug barons clandestinely recorded at the residence of the interdicted Police Chief, ACP Kofi Boakye.He said the state needs to improve its exhibit handling, as the drug menace is increasingly becoming a national crisis.Whilst describing the acquittal of the two as a blow to the country's fight against drugs, he stressed the prosecution must always present water-tight cases on drugs to the court, so they will not be thrown out.“Much more work needs to be done, because we have taken things for granted,” he said.Story by Nathan Gadugah/Myjoyonline.com/Ghana