OUI drug charges can be difficult for the Commonwealth to prove. This was evident in the recent case of Commonwealth v. Sousa, decided last week. In this case the defendant was convicted of OUI drugs and negligent operation of a motor vehicle after a bench trial in the Malden District Court. Bench trials are very common for an OUI drugs charge given the technical nature of the evidence and defenses.
After the guilty verdict, this case was brought to the Appeals Court. The defendant had appealed his conviction because he had believed that the Commonwealth presented insufficient evidence that the defendant was, in fact, under the influence of a prohibited substance. In reaching its decision, the Court relied on the decision of Commonwealth v. Ferola, which also found that the Commonwealth must presented particular evidence as to the substance it is alleged that a defendant is under the influence of to support a conviction.