New Use of Technology Shines Light on Strangulation

Before the use of alternative light source technology, it was difficult to prove that strangulation ocurred

September 02, 2010
By Kate Smith

To the naked eye, the white cloth appeared clean, save for a faint yellow outline that could easily be overlooked.

The forensic nurse removed a pair of tinted glasses from a sanitizing bag. As the hum of the machine filled the exam room, she turned off the lights. By shining rays of violet, blue and green light, she could see that a foreign fluid was present.

The alternative light source, known as ALS, has been used at Mercy Medical Center for years in sexual assault cases, giving investigators the means to detect the presence of bodily fluids on skin and clothing.

But now, the machine is being used more frequently in domestic violence cases that involve strangulation — a crime that previously had been difficult to prove.

The technology now being used at Mercy has not only given doctors a strong tool to aid victims, it's given police a powerful means to go after the attackers. And the more investigators learn about the machine, the more mainstream its use is becoming in domestic violence cases.

By just turning a dial and projecting different colors of light on the skin, "you can detect the extent of the strangulation; you can even see handprints around a victim's neck," said Lt. Vernell Shaheed, the recently retired commander of the family crimes unit of the city Police Department.

Nearly half the cases that go through the family felony violence division of the state's attorney's office involve strangulation, and that number is on the rise. The new technology means that more suspects can be charged with an offense, or a more serious offense.

Until recently, the four-year-old machine had been used only to detect fluids in sexual assault cases. But using the same technology, forensic nurses are able to reveal pooled blood beneath the skin on domestic violence victims. Because of its cost, however, only Mercy and one other hospital in Maryland have such a machine.

The increased use can help uncover more cases of strangulation. Without ALS, there is often little evidence of a crime. Ninety-seven percent of strangulation victims have no visible marks, according to Debra Holbrook, a forensic nurse at Mercy Medical Center

As a result of ALS, first-degree assault charges were brought in 62 cases last year, up from 16 in 2005. Prosecutors said most of the victims in those cases were evaluated with the ALS.