Glowing Future for New Evidence Detector


A detective heading into a crime scene slips on a backpack and modified 3-D video game glasses. After he waves a special light, once-invisible fingerprints begin to flash.

The portable evidence detector finds hidden semen too. Like fingerprints, semen gives off a fluorescent emission that is too weak to be seen but becomes visible with special lights and filters.

The technology to make the evidence glow is being designed at Sandia National Laboratories, a labyrinth of workshops better known for developing the nation’s nuclear weapons.

Assuming the technology works as intended, the possibilities are intriguing, said Ann Talbot, a lab director for the Albuquerque Police Department, which is working with Sandia to develop the product.


“It’s exciting--yes, we find it is indeed. It really will help us find things that we couldn’t before,” Talbot said.

Ultimately, it could lead to more convictions, she said.

Fingerprints now can’t be detected without using chemicals or fluorescing powders, so the technology could reduce the time searching for them by half, Albuquerque Det. Josephine “J.D.” Herrera said.

The device also has caught the attention of the FBI, which is interested in learning more about it, spokesman Paul Bresson said.


The technology employs lights and filters that flash at extremely fast rates. About twice a second, the glasses shutter open while the lamp flashes on. In that instant, most of the background light is drowned out and organic materials glow.

Too many, in fact. The detector also finds such items as paper, paint and fabrics washed in bleach. Researchers are solving that problem by testing filters and employing mathematical formulas that will pinpoint the evidence police need, Sandia scientist Colin Smithpeter said.

Talbot said she’s optimistic about the device’s success but is concerned about its sensitivity.

Police should not encounter crime scenes completely covered in fingerprints. Prints break down in about 100 days in dry climates and 10 days in extreme humidity. So old prints will disappear, and detectives using the detectors shouldn’t be overwhelmed, Smithpeter said.


“It will be a matter of the same problem they have now, where they pick up all the ones . . . and will still have several possibles and will have to match them up to the suspects,” he said.

Initially, the Sandia evidence detector will use a flashlight-size beam to scan for fingerprints and semen, but ultimately it could search for drugs and explosives, Smithpeter said. Different filters likely will be needed for searching for different evidence, he said.

The National Institute of Justice, the research arm of the Department of Justice, paid $393,000 for the technology. It will be marketed and sold by Molecular Technologies Inc. of Albuquerque. Ideally, the product will cost $5,000 to $10,000, which should allow most law enforcement agencies to afford a few of the devices, said Amy Gardner, MTI’s vice president of marketing.