A witness reiterated on Thursday that although she found a trace of nitrate — a major component of gunpowder — on a shirt purported to have been worn by one of three men killed by police on January 12, 2013 during an alleged shootout, she was unable to conclude that it was transferred to the garment during gunfire.

The witness — a retired lab analyst — while testifying on Wednesday in the murder trial of six policemen in the Home Circuit Court in Kingston, had told the seven-member jury that after testing swab samples taken from the hands of the three deceased and T-shirts belonging to two of them, she was not convinced there was enough evidence to definitively say that the nitrate on one of the T-shirts came from gunpowder. She told the court as well that no gunpowder residue was found on the hands of the men.

Nitrate, the witness said, is a component of the environment and can found in soil and could be transferred to a person if contact is made with it.