Mass. high court hears challenge over converting hospital serum ethanol into blood-alcohol evidence

The Massachusetts Supreme Judicial Court heard argument in Commonwealth v. Denny Gannett over whether applying a mathematical conversion to a hospital’s serum ethanol result constitutes a “chemical test or analysis” under the state’s operating-under-the-influence statute, G.L. c. 90, §24(1)(e), and therefore should be suppressed as nonconsensual evidence.

The question matters because, if the court adopts the defendant’s reading, prosecutors say a commonly used method to convert hospital serum ethanol readings into whole‑blood alcohol content (BAC) could be excluded at trial; the decision could affect OUI prosecutions across the Commonwealth.

Kevin Hennessy, arguing for the Commonwealth, told the court the statute should be read so that a mathematical conversion of an existing hospital serum ethanol result is not a new chemical test or analysis done “of the defendant’s blood.” Hennessy described the factual mechanics: the hospital’s laboratory produced a…