(CNN) -- The Aurora, Colorado, police officers involved in the fatal confrontation with Elijah McClain in August 2019 did not have a legal basis to stop him, frisk him or physically restrain him, according to an independent investigative report released Monday.
The report also questions the officers' statements about McClain's "superior strength," criticizes emergency medical responders' rash decision to inject him with ketamine and admonishes the police department for failing to seriously question the officers afterward.
"At the time of the (ketamine) injection, Mr. McClain had not moved or made any sounds for about one minute," the report states. "In addition, EMS administered a ketamine dosage based on a grossly inaccurate and inflated estimate of Mr. McClain's size."
On the whole, the 157-page report provides a critical view of Aurora's police and fire rescue teams for their roles in McClain's death. The 23-year-old Black man died three days after he was put in a carotid hold by police and injected with ketamine.
The Aurora city council funded the investigative report and hired Jonathan Smith, executive director of the Washington Lawyer's Committee for Civil Rights and Urban Affairs, to lead a review of the incident, according to Aurora.
The investigative team is expected to present its findings to Aurora's city council Monday afternoon. The city manager, police and fire chiefs and members of the investigative team then plan to hold a virtual news conference Tuesday morning.
McClain's death days after his interactions with police brought renewed scrutiny of the use of carotid holds and the sedative ketamine during law enforcement stops. His case gained renewed attention during Black Lives Matter protests over the summer in the wake of the police killings of George Floyd and Breonna Taylor.
What happened that night
McClain, a massage therapist, musician and animal lover, was walking home from a convenience store with an iced tea when he was confronted by three Aurora Police officers who were responding to a call about a suspicious person wearing a ski mask.
A police news release said McClain "resisted contact" with officers before a struggle ensued.
In officer body camera footage, McClain tells the officers, "I'm an introvert, please respect the boundaries that I am speaking."
"Relax," an officer says at one point, "or I'm going to have to change this situation."
Before an officer wrestles him to the ground, McClain is heard telling the officers he was trying to stop his music so that he could listen to them.
At one point, one officer tells another, "He just grabbed your gun, dude." One officer tells McClain that he will "bring my dog out and he's going to bite you" if McClain keeps "messing around."
Video shows an officer wrestle McClain to the ground. A letter from the Adams County District Attorney said an officer placed McClain in a carotid hold, which restricts blood flow to the brain. McClain briefly lost consciousness, the letter said, but continued struggling after officers released the hold.
Paramedics arrived and administered ketamine, the letter said. McClain was taken to a hospital but suffered a heart attack on the way, and he was declared brain dead three days later, the letter said.
DA declined to bring criminal charges
The autopsy conducted by the county coroner did not determine the cause of death but noted "intense physical exertion and a narrow left coronary artery" were contributing factors.
The autopsy report noted McClain's history of asthma and the carotid hold, though the autopsy did not determine whether it contributed to McClain's death. The concentration of ketamine in his system was at a "therapeutic level," the report said.
The McClain's family attorney, Mari Newman, has called the autopsy "very strange." She has said it "ignores the most obvious factor, which is a perfectly healthy young man is walking home from the drug store with a bottle of iced tea in a bag and he ends up dead."
In November of 2019, District Attorney Dave Young declined to press charges against the officers involved, citing the autopsy. "I cannot take a case to the jury where I don't know what the cause of death is on a homicide case," he told CNN's Chris Cuomo in June 2020.
But the Black Lives Matter protests this last year brought renewed attention to the case, and in June, Gov. Jared Polis appointed state Attorney General Phil Weiser to investigate as a special prosecutor. Weiser opened a grand jury investigation into McClain's death last month.
Three Aurora Police officers were fired and one resigned in July after photos leaked of officers taking smiling selfies and reenacting the carotid hold at a memorial site for McClain.
The death also brought closer scrutiny of the sedative drug ketamine, which has been increasingly used for law enforcement purposes on people experiencing "excited delirium." The Colorado Department of Public Health and Environment is reviewing its program that allows ketamine to be administered outside of hospital settings.
CNN's Leslie Perrot contributed to this report.