U.S. Capitol Police Officer Brian Sicknick, who engaged with pro-Trump rioters during the Jan. 6 insurrection, died of natural causes the day after the attack, Washington, D.C.'s chief medical examiner announced Monday.
Sicknick died after suffering strokes, the Office of Chief Medical Examiner, Dr. Francisco Diaz, said in a report. In an interview, Diaz told The Washington Post, which first reported on the determination, that Sicknick suffered two strokes.
Sicknick, 42, was sprayed with a chemical substance outside the Capitol at around 2:20 p.m. ET on Jan. 6, the report said.
He did not suffer an allergic reaction to the chemical irritants dispensed by rioters, Diaz told the Post, nor was there evidence of internal or external injuries.
At approximately 10 p.m., Sicknick collapsed at the Capitol and was transported to a local hospital. He died nearly 24 hours later.
Officials had said that Sicknick died a day after he sustained injuries during the attack. The Justice Department had opened a federal murder investigation into his death.
In a statement, the U.S. Capitol Police said it accepts the medical examiner's finding. "This does not change the fact Officer Sicknick died in the line of duty, courageously defending Congress and the Capitol," the statement said.
Sicknick has been counted as one of five people who died as a result of the insurrection attempt at the U.S. Capitol during which extremists — egged on by then-President Donald Trump and his acolytes in Congress — stormed the complex in an attempt to halt the certification of President Biden's White House victory.
Two men — Julian Elie Khater of State College, Pa., and George Pierre Tanios of Morgantown, W.Va. — were arrested last month over allegedly spraying a chemical on Sicknick. They were charged with conspiring to injure officers and assaulting federal officers and other crimes.
The Justice Department accused Khater of having asked Tanios to "give me that bear s***" during the riot, implying it was a pepper-based bear spray.
After pulling a canister from Tanios' backpack, Khater moved to the front of the crowd, next to the police perimeter. He then raised his hand, aimed the canister at Sicknick and two other officers standing a few feet away, and waved his arm from side to side, the agency said, citing video footage.
The three officers were immediately forced to retreat, "bringing their hands to their faces and rushing to find water to wash out their eyes," the Justice Department said.
It was not immediately clear how the medical examiner's report would affect ongoing investigations into Sicknick's death and how it might affect the charges stemming from his alleged assault. But the official ruling of his death from natural causes will likely make homicide charges difficult to justify.
"As in all the cases related to Jan. 6, the investigators will continue evaluate the facts and evidence against the law and charge accordingly," a Department of Justice official told NPR.