Autopsy results from the Dallas County Medical Examiner's office shows David O'Neal Brown Jr., had PCP and marijuana in his system at the time police said he shot and killed a Lancaster police officer and an innocent bystander on Father's Day.
The only son of Dallas Police Chief David Brown was shot nine times, according to the autopsy report.
PCP, also known as angel dust, is a powerful hallucinogenic that can cause schizophrenia, paranoia and violence when taken at higher dosages.
Barry Gustin, a toxicology expert and emergency physician in Berkeley, Calif., said the amount found in the younger Brown's blood -- 0.12 milligrams per liter -- is above the average listed in studies of people who have taken the drug.
"He didn't have enough to kill himself, but he had enough to be altered," Gustin said.
The amount of marijuana, 0.10 milligrams per liter, would be considered relatively low for someone using the drug recreationally, according to Gustin.
At about 11 a.m. on Father's Day, Brown's girlfriend called Lancaster police telling them he was having a "psychotic breakdown." Several officers responded to the domestic disturbance call at Brown's apartment.
On dashcam video Misti Conaway was captured telling police, "I mean he definitely needs some kind of help, psychiatric help."
"I don't know what he's capable of," Conaway told police.
Police spoke with Brown Jr., but left without arresting him. "Hopefully it'll be the last you'll see of us today," were the parting words of a Lancaster officer as they left Brown's Apartment.
Several hours later, at about 6 p.m. Sunday, police responded to a shooting in progress on the 900 block of River Bend Drive.
When Lancaster police officer Craig Shaw arrived, a grisly gun battle took place. In the volley of gunfire exchanged, both Shaw and Brown Jr., were killed.
The shootout occurred in common areas of the apartment complex. Another man, 23-year-old Jeremy McMillian, was killed prior to Shaw's arrival, Dallas County Sheriff Lupe Valdez said. Family members said McMillian was at the complex visiting his sisters and was shot multiple times in front of his girlfriend and newborn son.
The younger Brown had one previous brush with the law. He was arrested on suspicion of selling marijuana in Waxahachie in 2003, but he pleaded no contest and was convicted of a misdemeanor.
According to the autopsy report Brown Jr., suffered four gunshot wounds to the head, two to the neck, one to the left shoulder, one to the right thigh and one to the abdomen.
NBC DFW's Ellen Goldberg, Omar Villafranca, Lindsay Wilcox, Greg Janda and The Associated Press contributed to this report.
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