TARRANT COUNTY (CBS 11 NEWS) - Thomas Harper's attorneys say he's a devoted father who was trying to protect his children.
Harper is accused of killing a Good Samaritan after causing a multi-car crash that killed one driver, back in December of 2011. His trial started Monday morning.
Jurors heard frantic cries for help from a number of 911 callers.
"I heard a honk. As I look up I see a blue vehicle rear end us," witness Zach Treible told the court, adding, "hit us... kept on going with no signs of slowing at that point."
Investigators say Harper was speeding down Collins Street in Arlington, just a few weeks before Christmas. His two children were in the back seat of the full-sized SUV when he plowed into several cars.
At that point, investigators say 18-year-old Clarence Robinson went up to Harper's crashed out SUV to try and help the man's children.
Police say Harper pulled a gun and shot Robinson, who police describe as a Good Samaritan.
Defense lawyers presented the incident differently. Harper's lawyers say the father didn't want Robinson to touch his kids and even told the teenager to back off.
"We submit to you that the Good Samaritan sits right before you," defense attorney Ezekiel Tyson told jurors as he motioned toward his client during opening statements. "He [Harper] shot him, [Robinson] yes. He didn't shoot into the crowd. He didn't shoot into everybody on the scene. He eliminated the immediate threat to his family."
Prosecutors told the court that Harper is no saint and that he was high on marijuana when the incident happened.
Assistant District Attorney Amy Collum said, "He chose to try to help this man and his children after what appeared to Clarence to be a horrific accident. There is no justification for what he did and the people's lives he impacted."
A number of other witnesses are expected to take the stand this week.
Two other cases against Harper are still pending.
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