RALEIGH, N.C. — Security cameras are everywhere -- in stores, along highways and at red lights.

"They say a picture is worth a thousand words, maybe it's worth a thousand witnesses," according to Wake County District Attorney Colon Willoughby.

Willoughby said security cameras convinced a jury to convict William Jones in a 1987 convenience store robbery. The video shows Jones shooting three people, killing one.

"It really portrayed to the jury exactly what went on and what this crime scene was like as opposed to saying, 'this man is dead,'" he said.

The evidence also has its limitations. The story told on a tape is only as good as the quality of the video. Details, such as color, are often limited.

"What happens with a lot of people is they don't keep the tapes in them, tape runs out or employees forget to change tapes," said Wake County sheriff Donnie Harrison said.

Harrison said the camera can sometimes be the smoking gun and are not just for criminals.

In Cincinnati, cameras mounted on police cars provided the public with an extra eye in a fatal scuffle between police and a drugged-up suspect.

Harrison wants to put cameras in every Wake County deputies' car.

"It shows what we go through and what really happens at a crime scene," he said.

A view to a crime is often the key to solving it.

Surveillance video is not always admissible in court. A judge will usually not allow it if the video quality is poor.