Suffolk County District Attorney Daniel F. Conley last week presented two mechanical engineering doctoral fellows with plaques thanking them for their “efforts to reduce gun violence and improve the quality of life in our neighborhoods.”

Conley’s office on Friday presented the plaques to Priam Pillai and Adam Wahab, both of whom are pursuing doctoral degrees at the Massachusetts Institute of Technology, to thank them for their work with the DA’s Gun Prosecution Task Force. Both men have testified as expert witnesses in the Suffolk County Gun Court, which fast-tracks cases of unlawful firearms possession and boasts an overall conviction rate of almost 90%.

Pillai and Wahab have told judges and juries about the science behind thermal imaging devices such as the Bullard TI Commander, which records heat output the way a conventional camera records reflected light: when the device is trained on a recently-discarded handgun, the body heat retained by the gun’s metal frame shows up as brighter than the area surrounding it. This can be used to corroborate a police officer’s observations that a suspect was carrying and tossed a firearm, and can dispel a claim that a recovered gun had been in place and untouched for an extended period of time.

This use of thermal imaging in law enforcement was pioneered by Boston Police and Suffolk prosecutors.

“Priam and Adam perform a tremendous service to the public for no payment and no compensation,” Conley said. “As consultants and expert witnesses, they’re putting a powerful tool in our prosecutors’ toolbox. When every gun conviction takes a potential shooter off the street, there’s no telling how many violent crimes we’ve averted by targeting those with illegal guns and the willingness to use them.”

Thermal imaging technology, pioneered for military purposes and now used mainly as a firefighting aid, was first used as a law enforcement tool when the Boston Police Department purchased the Bullard device several years ago. Although the technology has existed for decades, however, Massachusetts courts had refused to allow it as evidence until Conley’s office developed expert witnesses to testify regarding its accuracy.

Toward that end, prosecutors reached out to experts in thermodynamics and related fields at MIT. Pillai and Wahab, who hold master’s degrees and teach classes at the renowned Cambridge university, were selected as potential expert witness after a rigorous evaluation of their professional, educational, and ethical qualifications.

Suffolk prosecutors then led extensive pre-trial voir dire and evidentiary hearings in a series of efforts to have them qualified as an expert witness. Those efforts were successful, and both have since testified as court-certified experts in heat transfer technology in bench and jury trials. But for the prosecutors’ work to bring the thermal images and the science that supported them into evidence, Conley said, winning convictions would have been much more difficult.

Late last year, the very first jury trial to use thermal imaging as evidence in a gun possession trial ended in a conviction for JOSE E. RODRIGUES (D.O.B. 6/30/84). In that case, Boston Police observed the suspect clutching his waistband as he walked along Whittemore Street on the evening of Jan. 12, 2009. When they inquired of him, he ran away. Officers gave chase, losing sight of him briefly before spotting him with an arm outstretched as if having thrown something; they finally took him into custody in the side yard of a Glendale Street residence. Along his path of flight, they recovered a 9mm semiautomatic Smith & Wesson handgun.

In addition to taking conventional photographs of the weapon, Boston Police deployed the Bullard TI Commander and took thermal images of the gun and the area around it. These were the images presented to the jury. Pillai testified in that case about the science of heat transfer upon which the Bullard’s technology is based.

“Prosecutors talk about the ‘CSI Effect,’ or the expectation of modern juries that extraordinary scientific testing goes into every street-level arrest,” Conley said. “That’s generally an inaccurate assessment, but thermal imaging is one way we really can bring the cutting edge into the courtroom.”