This story begins about 15 miles away when 17-year-old Anthony Bentley was driving near his home in west Houston.
Bentley always wanted to be a police officer and was a member of Houston Police Explorers, a mentorship program for young people.
While he was driving, Bentley says he got a message from his lead advisor, asking students to keep those officers in their prayers.
"(Bentley) files that away in his head. Then about a block from his house is hit by a guy who's going at a high rate of speed," said Joseph Gutheinz, Bentley's attorney.
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That guy, according to police, was 17-year-old Derrick Green.
Green is accused of stealing a car and leading police on a chase.
Gutheinz admits that Bentley followed Green a short distance.
When Green crashed, he allegedly ran and Bentley grabbed the gun under the seat of his car.
"As he's running, he slows down and turns," Gutheinz said. "All Anthony Bentley could think of is that if he's the guy who just shot two police officers, he is going to turn the gun on him."
He says Bentley fired and hit Green three times.
"It was never his intent to do anything but help the police by directing the police to which direction he went in the neighborhood," Gutheinz said. "The shooting was totally unforeseeable."
The District Attorney disagrees.
Bentley has been charged with aggravated assault with a deadly weapon.
And, in a statement, the DA said additional or different charges could be coming once the case goes to a grand jury.
Green's family and community activist Quanell X are fighting to bump up that charge to attempted murder.
"Who gave this young man the permission to become judge, jury, and executioner out here on the scene? This 17-year-old man, Derrick Green, was wrong for being in a stolen car. That's why we have a court system," Quanell X said.
Green remains in intensive care at Ben Taub Hospital.