Sometimes, a sketch can be the best clue police have to solve a crime, but getting that composite image requires not just a witness, but a special type of artist.
In Berks County, that role most often rests with Wyomissing police Sgt. William Roecker, who broke down the process for 69 News.
"We use the FBI's facial identification catalog," he said. "There's a section on eyes, a section on nose, ears, shapes of the head, hair, skin irregularities, cheek bones, chins."
Using the catalog, Roecker said he'll sit down with a crime victim or witness and have him or her look through the pages, carefully studying the various facial features.
Based on which options they believe best resemble the suspect, Roecker will start drawing the eyes, then the nose, then the mouth.
"That's called the facial triangle, and that's basically where the identification is going to come from," Roecker told 69 News.
Roecker said his sketches have led to arrests in state and federal crimes. He said he's drawn several composites outside of Berks, including in Lancaster and Lehigh counties.
"The composite is only as good as the recollection of the witness or the victim and how they can relay it back to me when they're looking at the features," Roecker said.
Most recently, Roecker created a sketch of a robber in Sinking Spring. Based on recent averages, he'll likely hand-draw another five or so this year, nearly half the amount he'd create years ago.
Roecker said he was first trained in 1982, and in years since, hand-drawn composite sketching has become somewhat of a dying art. That includes sketching composites of age progression and facial reconstruction, in which he is also trained. Most of his experience, however, involves criminal facial composites.
"I used to do 12 to 15 a year, but that's down pretty much now," he said.
It's a trend resulting from increases in digital programs and video surveillance, but when those methods fail or are unavailable, Roecker can provide his unique, effective talent.
"It's very successful… if the composite is pretty much right on, somebody's going to recognize this person one way or the other. Everybody knows somebody."