A forensic scientist testified yesterday at the triple-murder trial of two Mexican immigrants that a newly discovered "blue granular substance" from the crime scene could not be identified - meaning what could have been new evidence is more likely a nonstarter.
Policarpio Espinoza, 24, and Adan Canela, 19, are on trial for a second time in Baltimore Circuit Court on charges that they murdered three young relatives in May 2004. Their first trial ended last summer in a hung jury.
Prosecutors asked the Baltimore Police Department crime lab to re-examine several pieces of evidence in October, after the mistrial, and a lab worker testified Wednesday that she spotted a blue substance on several articles of clothing from the crime scene in Northwest Baltimore.
Yesterday, David L. Exline, a senior forensic scientist with a Pennsylvania-based private laboratory, testified that he analyzed the blue substance and could not determine what it was.
He said it had the consistency of toothpaste or icing but that its chemical components - mainly gypsum and kaolin - seemed more characteristic of a construction material. Testimony at the first trial showed that Espinoza sporadically worked construction jobs in Bel Air, but jurors have not heard about that during this trial.
Exline said he compared the blue substance to two kinds of cement used by a company in Maryland and that they were not the same.
"In the end, I still couldn't find a material that it matched to," he said.