THE ADVANCEMENT OF FINGERPRINT TECHNOLOGY

Excerpted from ENN EMERGENCY SERVICES REPORT-Wednesday, June 11, 1997 Vol. 1 - 162

THE ADVANCEMENT OF FINGERPRINT TECHNOLOGY ...
By Steve Macko, ERRI Crime Analyst

In the murder case of a cabdriver earlier this spring, a bloody fingerprint found on a gate led Chicago police to the correct suspect. That same fingerprint helped eliminate two men that police were questioning in the homicide.

Lt.-Colonel Laurence Mulcrone, the lab director for the Illinois State Police Forensic Science Center in Chicago, explained, "The gate was brought over to the crime lab. We photographed it and developed the print ... compared it to the suspects' and determined that neither suspect matched the fingerprint. We then entered the fingerprint into the automated fingerprint identification system and got a positive response. We gave it to the Chicago Police Department and they went out and made an arrest. We're becoming much more successful in developing these leads for the detectives."

The Illnois State Police Forensic Science Center is using state-of-the- art techniques to analyze fingerprints. According to Mulcrone, fingerprints "provide excellent leads for investigators. They also help detectives avoid leads that are going nowhere. We can help clear people as well as provide leads for suspects."

Dusting a crime scene with special powder to find latent, or hidden, prints and remove them with adhesive tape is the old-fashioned and time-tested method that is still used by evidence technicians. Today, there are other methods available for finding latent prints at a crime scene. These newer methods use ultraviolet light, lasers and super glue. Computers can now automatically compare prints against millions of others in a database.

Federal Bureau of Investigation Special Agent Bob Long is the spokesman of the Chicago Field Division. He said, "We've gotten a little more advanced in our abilities to pull prints from surfaces that might have been difficult, if not impossible -- like tissue paper -- unlike a smooth, polished desk top where you can see your fingerprints without dusting, some surfaces don't lend themselves to that kind of situation."

The Illinois State Police Forensic Science Center, located at 1941 West Roosevelt Road in Chicago, is one of the most advanced crime labs in the country. It analyzes evidence for the Chicago and its suburban police departments.

Jim Fazekas, the latent prints supervisor of the lab, says that an image enhancement system at his lab can remove background that makes it "easier for us to see the fingerprint."

The lab also uses a "super glue chamber" that permanently bonds fingerprints to non-porous objects. Inside the chamber, explained Fazekas, super glue is heated so the fumes adhere to the fingerprint, highlighting the ridges for comparison to a suspect's prints. It is believed that this process was recently used in the Andrew Cunanan case, in the murder he is suspected to have committed in Chicago.

Another method being used is finding latent prints by applying laser dye to an object that is viewed with a laser. Ultraviolet can also be used to reveal prints.

Fazekas said, "Fingerprint technology has grown more in the past ten years than it did in the first 100 years. But the time that it takes to work a case in the lab is longer because of the additional tests we have to do."

In a typcial case, technicians match the prints to find out who was at a crime scene. "Sometimes an individual has access to the home, so putting that individual in the home isn't going to mean anything," Fazekas explained. "The majority of our identifications are eliminating the fingerprints belonging to the victim or the victim's family members."

According to Fazekas, once those prints are eliminated, the remaining prints are photographed and entered into the automated fingerprint identification system, which is a computer database of fingerprints from three million people arrested in the state of Illinois.

The system will then generate a list of ten possible matches and then it is up to the technicians to determine if there is a match. Many times there isn't a match. At one time, this task was almost impossible to accomplish because no person could review all fingerprints that are on file.

Currently, the Illinois crime lab cannot search the fingerprint databases of the FBI or other states. Fazekas said that Illinois is working with neighboring states so that they can search each other's databases.

Sergeant Paul Carroll, the commanding officer of Chicago's crime analysis unit, said that a fingerprint "can be the greatest thing ever. We've had cases over the years where we get the offender's fingerprint in the victim's blood. Evidence doesn't get any stronger than that. We've got people in jail for murder with nothing more than a fingerprint."

Fazekas said that the quality and presence of fingerprints depend on several factors ranging from the weather to the way a person perspires. He said, "More times than not, our latents are just a partial fingerprint. Does a person always leave behind an identifiable fingerprint? No. Some people sweat more than others. Sweat is a part of it. When you touch your hair or your nose, you're transferring grease and oil to your fingers." which Fazekas explained, will enhance the chances of a fingerprint being left behind.

He added that it also depends on the surface that was touched. Fingerprints, of course, can be easily lifted from glass, metal, wood, leather and vinyl. But it is almost impossible to get prints from rugs and fabrics.

According to Fazekas, "The receiving surface has to be smoother than the fingerprint. I've been surprised a few times. I do remember there was a bloody print on a bed sheet and usually a print on that surface isn't good."

It can also be, at times, difficult to find fingerprints even on a smooth surface. Sergeant Carroll explained, "Atmospheric conditions have a lot to do with this. If it's raining, it's hard to get prints. If it's real cold, there's no moisture, so it's hard to obtain prints. Auto theives are real big on leaving cars out when it rains because they know we can't get prints."

The ENN EMERGENCY SERVICES REPORT is a subscription publication of the EmergencyNet NEWS Service, which is a part of the Chicago-based Emergency Response and Research Institute. This publication specializes in Law Enforcement/Fire/EMS/Disaster and Medical Issues.

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