Foster & Freeman USA Inc., a United Kingdom-based company with its U.S. headquarters in Sterling, Virginia, maintains SoleMate along with two related forensic print databases: TreadMate and Crimeshoe.com. With a database of more than 6,000 entries, TreadMate helps investigators identify tire tracks and provides manufacturer and other details. Identification is done through pattern matching using the database and either a special viewer program or through use of Foster & Freeman's evidence management system.
Michael Zontini, applications engineer with Foster & Freeman, explains that investigators search tread characteristics in the database. Based on the information that is known, such as a rain channel pattern, TreadMate returns potential matches. SoleMate, which Zontini says has more than 19,000 entries in its database, is searched similarly, by identifying known features from print evidence.
Mankevich, who has been using SoleMate through the SICAR evidence management application with the Maryland State Police since 1999, says the program helps he and the three other footwear and tire track examiners act as a communications hub for area investigators.
"It helps link crimes that have the same shoe prints appearing repeatedly," Mankevich says. "They may be investigated by different law enforcement agents who would not know and are not in communication with each other. We're the ones that put all the players in contact with each other. I may have a burglary from March investigated by the Maryland State Police and then in April, a county sheriff's office in the same county also submits evidence to the laboratory here, and it turns out they have the same shoe print appearing in both cases."
Mankevich says it may be coincidental that the same shoe print appears in various cases. But in case it isn't, he is able to alert each investigator so they can collaborate and swap information.
Crimeshoe.com is a service the company offers for smaller agencies, or agencies that may need to analyze and identify shoe print evidence on a limited basis. Instead of purchasing a license for SoleMate, an investigator can submit an image to Crimeshoe.com online and receive results back via e-mail — usually within 24 hours, Zontini says — for a fixed charge. SoleMate and TreadMate also have potential for expansion through an agency's self-populated local database and can be linked with other agencies' databases, too.
Foster & Freeman's staff of researchers continually update the tire and shoe databases, working with manufacturers and coordinating additions based on new product releases.
Mankevich believes the only way the program could do better would be to become a nationally linked system.
"The heart-wrenching thing about it is that it's not linked nationally with these other databases, you know, like fingerprint, DNA and firearms," Mankevich says. "It would really close out a lot of cases. You wouldn't have a repeat offender getting away, because just as quickly as we pick up the repeat offender with fingerprints now, you would pick up the repeat offender with the shoe prints."Shoring up the glass evidence valley
The Miami-based Glass Evidence Reference Collection works a little differently than the Foster & Freeman databases. Jose Almirall, founder of the database, created it for the Technical Support Working Group, a program under the U.S. government's Combating Terrorism Technical Support Office. Unlike other search-and-comparison databases, such as AFIS or SoleMate, the purpose of the glass evidence database is to compare chemical analyses of separate glass evidence and determine if they are from the same source.
"The purpose of this database is to say: of all these 750 glass samples, we're able to distinguish all of them from each other unless they came from the same plant made around the same time," says Almirall, who has been working with glass analysis for 15 years. "It is meant to give us an idea of how frequently we would find two glass samples that have the same composition, but came from different sources. And the answer to that is: we don't."
Almirall, an analytical chemist and director of the International Forensic Research Institute at Florida International University, says that through determining elemental composition of glass evidence, source matching is possible. That means if two glass samples have the same elemental composition, they came from the same manufacturing source. Almirall says the database has helped to "shore up the valley of scientific glass evidence."