Matsumur, Fuseo (World of Forensic Science)
TRACE EVIDENCE EXAMINER
Louis Pasteur, the nineteenth century medical researcher, once noted, "Where observation is concerned, chance favors only the prepared mind." And so it occurred, almost a century after Pasteur's death, that an ordinary trace evidence examiner in Japan made a rather profound observation. In 1977, Fuseo Matsumur was preparing microscope slides for an investigation being conducted by the Japanese National Police Agency. The crime involved the murder of a taxi driver, and Fuseo's task was to glue hair samples from the crime scene to glass slides for later microscopic examination. While carrying out this routine task, Matsumur made a seemingly simple observation: the fumes from the Superglue® (cyanoacrylate adhesive) he was using caused his fingerprints to become visible on the glass slides.
Fingerprint "dusting," the print retrieval technique commonly seen on television, is somewhat limited in its use, because the perspiration which forms a fingerprint evaporates rather quickly, leaving nothing to attract and hold the dusting powder. Long after the moisture in a fingerprint has evaporated, however, the amino acids found in human sweat remain behind, sometimes for months. These amino acids attract the fumes from Superglue® and other brands of cyanoacrylate adhesive, forming a sticky image of the latent print, which is then dusted and lifted with a wide piece of transparent tape.
While Matsumur knew none of the science behind what he had observed, he recognized its potential importance in the field of criminology. Matsumur quickly relayed his observation to Masato Soba, a print examiner at the agency, who began exploring the technique further. Soba's subsequent work, along with that of researchers in other organizations, has led to numerous advances in this technique, though the basic concept remains unchanged. A typical analysis today involves placing the evidentiary objects inside a sealed box with an open container of cyanoacrylate. The glue is heated to release its fumes, and after about 15 minutes, when the prints have become clear, the box is pumped clear and the objects are removed and dusted. Prints discovered using this method can be removed with tape and placed on a transparent plastic card.
"Fuming" has become a routine procedure in criminal investigations today, allowing investigators to collect otherwise unusable latent prints.
SEE ALSO Crime scene investigation; Fingerprint; Latent fingerprint.