Gardai use computerised photo fit

There are many technologies which can be used to link suspects to evidence or a crime scene and these technologies help to solve crimes. SCOPE investigates two of these at the Garda Technical Bureau at Garda Headquarters in Dublin.

The first type of technology is used to draw faces. When a person witnesses a crime, and gardai are trying to catch the criminal, they can create a computer generated image of the suspect, from talking to the witness. This image can then be sent around to investigators and sometimes to the media, to help identify the suspect.

Detective Sergeant David Conway at the Garda Technical Bureau shows SCOPE how the computer programme that does this, called Profit, is used. “This is the modern version of the old photo fits which you might have seen on the TV,” he says. “It did the job in its day but technology has overtaken it and its really not any comparison to what we have now.”

Facial characteristics

The gardai start by interviewing a witness and asking him or her to describe the suspect. They then put the information from the witness into the computer. They start with a facial template - a starter face which usually doesn’t look much like the person they are looking for but is based on a basic description such as “dark hair” or “tall”.  

Gardai then add various details such as shape of face, hair style, colour of eyes and so on. Then each characteristic is adjusted on a scale. The gardai work with the witness, changing the image on the computer so that the end result is a likeness of the suspect.

Finally, the photo is ready to be circulated and hopefully from this, criminal will be recognised and caught.

Shoe science

Another piece of evidence which can help investigators is shoe prints. SCOPE visited the shoe print laboratory at the ballistics section of Garda headquarters to find out how the shoe print technology is used to link a suspect to evidence.

According to Detective Garda Sharon Mooney, shoe print evidence is important because each shoe print has certain characteristics.

“There’ll be characteristics which will be common to the make of the shoe,” say Sharon. “There will then be individual characteristics. Maybe little imperfections that the shoe may have picked up. through wear and tear.”

System

The detectives use a system called SICAR (Shoe Identification and Retrieval. They take photos or cast impressions of shoeprints at a crime scene then scan the image into the computer.

First the pattern can be used to find out what type of shoe the print has come from. Gardai search using the “solemate” database - a database of shoe prints from all the shoe types that can be bought in Ireland.

They can also search the crime database, to see if the shoe has been linked with another crime. Computerised face fit creation and shoe print matching mean that two of the oldest crime-fighting tools have the benefit of modern technology.

Learn more:

Visit the Garda Technical Bureau on the web

Read about the Profit system
[http://www.abm-uk.com/uk/products/profit.asp]

Find out more about the solemate database