The sketch of the Baton Rouge serial killer is posted on phone poles and in windows around the state, but many wonder just how accurate these “person of interest” sketches are.
In recent years, law enforcement departments have adopted several ways to produce composites and sketches of potential suspects and to ensure their accuracy as much as possible.
The New Orleans division of the FBI uses a traditional sketch artist to put together a composite, said Agent Sheila Thorne.
“What we do is seek out and identify a reliable and credible individual who has been tested in court to serve as a sketch artist,” Thorne said.
The accuracy of the sketches relies solely on the recollection and reliability of the witness, Thorne said. The sketches are only as reliable as the information, she said.
There is no guess work involved when creating composites.
“The artist uses their expertise to put together a composite based strictly on what the individual is providing,” Thorne said.
Sketches are a valuable tool for investigation, she said.
“We use them when deemed necessary to utilize all the resources we have,” she said. “It just depends on where the investigation is led to.”
Thorne said the FBI also has various databases in which ongoing investigations can be compared to each other to see if there are any similarities, if any cases are related or if it is dealing with a repeat offender.
Similarly, the Baton Rouge Police Department uses a police officer who is trained as a sketch artist, said Cpl. Don Kelly, BRPD spokesman.
“We think it’s a beneficial system,” Kelly said. “We’ve been happy with the success that we’ve had using our sketch artist.”
As compared to computer programs, using a sketch artist allows better flexibility, and there is a greater likelihood of getting an accurate picture, Kelly said.
Sketch artistry is not something that can be taught to just anyone, Kelly said.
“They need an artistic ability to be technically proficient as a sketch artist,” Kelly said. “It’s also very helpful if they have the ability to interview and work with witnesses.”
There is a lot of collaboration between the artist and the witness, Kelly said.
“It’s one thing to sit there and look at someone and draw them, but what our artists have to do is much more difficult than that,” he said.
The witness is usually describing someone they have only seen once before and under stressful circumstances, Kelly said. The artist learns how to draw out specifics and work with the witness about what they have seen, he said.
“Generally, the goal is to get a sketch that is close enough to jar someone’s memory or at least get someone thinking,” Kelly said.
The LSU Police Department uses a computer program instead of a traditional sketch artist to produce its composites, said LSUPD Capt. Mark Shaw.
“We have commercial software that we use called FACES,” Capt. Shaw said. “The program applies extensive previous research to guide us step-by- step to create an initial picture of that person of interest.”
Shaw said he has seen many composite drawings that have turned out to be extremely accurate portrayals of the criminals apprehended.
“Some of the sketches that we’ve done could literally be a black and white photo of the suspect,” he said.
Using a computer program such as FACES removes the need to have artistic ability when creating composites, Shaw said.
The generated composite can easily be passed on via code to other departments and media sources that have the FACES program, Shaw said. This allows LSUPD to pass on the exact composite to a second party without losing quality through scanning or faxing.
Shaw compared the human mind to a camera that constantly takes pictures but sometimes needs help recalling those images. The FACES lab helps victims and witnesses do this, he said.
“We ask specific questions prompted by the computer that trigger the recall of information,” Shaw said. “It gets the victim out of those thoughts of fear and into doing something familiar.”
At the end of the interview, not only is a sketch produced, but information is recalled that may not have been remembered otherwise, he said.
After the initial composite is generated, the victim or witness can compare that sketch to their memory and change anything that is incorrect, he said.
The accuracy of these composites can be further improved by comparing sketches from different incidents and looking for likenesses, Shaw said.
Through this, LSUPD may discover that two or more situations may be linked to one perpetrator or one “person of interest,” he said. LSUPD may then get the two witnesses or victims together to compare and contrast their initial sketches and create another more accurate sketch.