MARIETTA - Cobb Officer Pete Jones, an investigator in the Selective Traffic Enforcement Program, is only the second person in the county - and one of only 700 in the world - to be certified by the Accreditation Commission for Traffic Accident Reconstruction.

Jones endured more than eight hours of testing, including reconstructing a staged collision, to earn the certification.

"I wanted to do this because it's nice to have an outside agency that has signed off on me and said that I know what I'm doing," he said. "We don't need the accreditation to testify in court or to be considered an expert on crash reconstruction, but it goes to your credibility on the stand."

His achievement is also earning him accolades.

"Officer Jones is an excellent police officer and traffic investigator," Police Chief G.B. Hatfield said. "As a member of ACTAR, he has met the highest standards in the industry. It is a very unique honor, and the police department is very proud of him."

Jones, 36, has been an officer with Cobb's STEP unit for nearly six years and holds a bachelor's degree in mathematics from North Georgia College. Jones and his wife, Jenny, are the parents of Owen, 7, and Emily, 4.

He quickly became interested in Cobb's STEP Unit after joining the force as a rookie in 1997, he said.

"In Cobb, you have to work at a precinct when you first get out of the police academy. During your first few years as a police officer, you kind of tend toward one job area. I always leaned towards traffic enforcement and accidents," he said. "My favorite part is the closure and being able to figure out physically and scientifically what made the accident happen."

There are nine investigators in Cobb's STEP Unit and they are called to the scene of traffic accidents when there is serious injury or death. From there, they divide tasks. One investigator interviews witnesses; another may draw a rough sketch of the accident. The investigators employ mathematical and physics formulas to determine various factors of the accident, from speed and drag factor to crush and momentum. The investigators typically spend about two weeks on an accident report before it's turned over to the district attorney.

They don't like to rush their work, said Officer J.D. Lorens, an investigator in the STEP Unit for nearly five years.

"Let's face it. The part of the job we do is fatality wrecks, and that touches someone. I've personally been touched by a fatality wreck. We can't tell them why someone drank too much or was speeding, but we can tell them what happened in the wreck, and sometimes they find solace in that," he said. "I appreciate the fact that we get time to look at everything and run down every lead. When the file is complete, it has to be accurate. You don't want to change your answers, because this is what the district attorney uses to prosecute people."

There are about 18,000 traffic accidents in unincorporated Cobb each year, the officers said. Last year, 45 of those wrecks resulted in a death. There have been 19 traffic deaths in Cobb so far this year.

Knocking on a door to tell someone that a loved one is dead is the worst part of the job, Jones and Lorens agreed.

"It's the middle of the night and they're expecting their family member home. They should have been home two hours ago and they're worried because they're not picking up the cell phone," Jones said. "Then there's a police officer knocking at the door. They pretty much know. It's their worst fear come to life when we're there knocking at their door."

Added Lorens: "It's especially difficult when you have to tell them it wasn't their loved one's fault - that it was completely the fault of someone else."

Jones said he now realizes that being in an accident often boils down to luck.

"To be involved in an accident or not, a lot of it is luck. It's being in the wrong place at the wrong time. It's a matter of split seconds, feet and inches," he said.

The unit's ability to investigate those final seconds and come to a factual conclusion is elevated now with Jones' accreditation, Lorens said.

"It's really a feather in the cap for the department," he said.

Around the world, 700 people are ACTAR Accredited Reconstructionists, and all must complete continuing education classes to maintain their status. Danny Doyle, a private accident reconstructionist who founded Doyle & Associates, Inc., is the other Cobb resident to have the certification.