By Brad Edwards

(CBS) – A 12-year-old girl who fought off an attacker in unincorporated Des Plaines this week told investigators enough details to generate an elaborate sketch of the suspect.

CBS 2’s Brad Edwards reports on the collaborative process between victims and police artists that helps nab offenders.

Det. Timothy McPhillips of the Cook County Sheriff’s Department says the process includes referring to a book with a wide variety of facial features. But the renderings are not cut-and-paste jobs.

It’s also not “hocus pocus,” McPhillips says.

“There’s a science to it,” he says.

McPhillips did not do the sketch publicized this week from the Des Plaines attack. But he’s had plenty of experience sketching suspects that have led to high-profile arrests.

One of the cases he worked on involved an iPhone thief who pushed a woman to her death at a CTA platform.

His ultimate goal: give the victims a voice.

“I tell them, when you’re talking to me and doing a sketch, you’re already starting the healing process. Now you’re fighting back,” McPhillips says.

In the assault earlier this week, the 12-year-old sixth-grader fought off the man who attacked her in a wooded area and bit him on the finger when he tried to cover her mouth.

Cook County Sheriff’s police said Friday they’ve narrowed a list of suspects to just a few.

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