The unknown killer left his DNA at the scene, but it hasn’t helped Aurora Police detectives much until now.

Aurora Police solicited the help of a DNA technology company to create an image of the suspect who viciously attacked and murdered three members of the Bennett family in 1984.

“It’s one of the older, unsolved cases that we have,” said Aurora Police Detective Steve Conner, who’s been working on the Bennett case for about nine years.

In January 1984, a man broke into the Bennett’s Aurora home and used a hammer to bludgeon Bruce Bennett, his wife Debra and their seven-year-old daughter, Melissa, to death. Three-year-old Vanessa survived the attack.

“There were no witnesses that we came across that said we think it was that person or we saw this,” Detective Conner said.

A break in the case came in 2002 when investigators were able to collect DNA evidence that had been preserved at the scene. That same evidence was recently sent to Parabon NanoLabs, a Virginia company that specializes in what’s called DNA phenotyping.

“From the DNA, they were able to I guess produce a composite – an image of what that person may look like,” Conner said.

The company uses DNA like a blueprint to make predictions about a person’s appearance including hair color, eye color, skin tone, face shape – even whether the person has any freckles.

“If you’d asked me five years ago, I’d say no way. I mean how can you produce something from DNA?” Conner said.

The technology is able to help detectives like Conner narrow down suspects.

“I can eliminate certain races or ethnicities based upon the image they gave,” he said.

Aurora Police are still looking for John Doe, the suspect in the Bennett family murder case. Detective Conner is hopeful the new composite will lead to an arrest.

“This is something that, for us, we’re excited about because it puts a face or an image to a person we’re looking for,” he said.

Aurora Police said the technology was too costly to use in every case. Detective Conner said he expected the technology would improve and become more affordable in the next five years.