Published: Aug 28, 2013 1:00 PM EDT
Updated: Aug 28, 2013 8:12 PM EDT

CAPE CORAL, Fla.- For the first time we're seeing surveillance video taken seconds before a door to door salesman was killed last year in Cape Coral.

Kenneth Roop is on trial for shooting Nicholas Rainey to death and his lawyers say he acted in self-defense. Roop's attorney says his client didn't know why Nick Rainey was in his driveway, and shot him as he approached, because he didnt know his intention.

Was is a cold blooded killing? "Seconds pass, boom. He puts a bullet in the back of Mr. Rainey's head," said Assistant State Attorney Andreas Gardiner.

Or self defense? "He thought Nicholas Rainey was coming into this truck to get him," explained defense attorney Marquin Rinard. 

Witnesses and evidence in Kenneth Roop's murder trial, like a bloodied shirt, depict the last day of Nick Rainey's life.
What drew the most emotion from the Rainey family, was video recorded the day of the shooting, from the defendant's own home surviellance system.

Rainey in a white shirt walks up to Roops front door. There's no answer, so he walks down the driveway, when Roop pulls up in a truck. Next there's the shooting, just off screen. Then, you see Roop's truck speed up into his garage, where he is moments later taken down by an off-duty Collier County deputy.

"Roop seemed agitated. He wasn't happy about anyone being there," testified Sgt. Kristin Shiner, with the Collier County Sheriff's Office.

 The jury also saw photos of Rainey's body. One photo showed a meat flyer laying under Rainey's arm.