It began just like every other Fourth of July parade, the witnesses said on Wednesday.
In a small courtroom in Lake County, Ill., they recalled the details of the day nearly three years ago with quiet clarity: the high school marching band strolling through downtown Highland Park, the families gathered in their usual spots along the parade route, the police officers directing traffic.
And then, witnesses recalled, they heard a popping sound, over and over, coming from a rooftop.
“It went from watching a parade to utter chaos,” said Dana Ruder Ring, a Highland Park resident who testified that she grabbed her children and ran for their lives when she and her husband realized that a shooting was unfolding.
There will be no trial for the shooter, Robert Crimo III, who pleaded guilty in March to 69 criminal counts, including murder and attempted murder, in the deaths of the seven people killed on July 4, 2022. The authorities said that Mr. Crimo, then 21, had climbed onto a rooftop in Highland Park, a suburb north of Chicago, and fired into the crowd below with a high-powered rifle. He fled in the aftermath but was arrested in a nearby town hours later.
Instead, Wednesday was the start of Mr. Crimo’s sentencing hearing, one that could stretch for two or more days so that witnesses and victims can tell their stories. No sentence has been decided yet. Using photos, videos and drone footage, prosecutors established how Mr. Crimo committed the crime, how law enforcement officers responded and how the Highland Park residents who witnessed the shootings still feel the anguish.
Family members of those killed packed the courtroom, watching testimony intently and occasionally dabbing away tears.
They did not have the opportunity to address Mr. Crimo directly, since he remained in the Lake County jail and did not attend the sentencing hearing. His lawyers noted his absence and said that he did not wish to attend.
“We will proceed with the sentencing without him being present,” Judge Victoria A. Rossetti of Lake County Circuit Court said as the hearing began.
The judge is expected to issue a formal ruling after all testimony is given in the coming days, but under Illinois law, Mr. Crimo will be sentenced to life in prison without the possibility of parole.
Cmdr. Gerald Cameron Jr. of the Highland Park Police Department was the first to take the witness stand, recalling his original task that day: diverting traffic and helping manage the crowds of thousands of people who arrived to attend the parade.
Then Commander Cameron heard gunshots from the rooftop. “People were running, yelling, screaming for help,” he said.
A man lay in the street, bleeding. A woman was nearby, covered in blood, with a bullet wound to her abdomen. As paramedics reached the area, Commander Cameron said, he began transporting victims to a nearby hospital.
After he returned to the scene, Commander Cameron and other police officers escorted frightened parade attendees who had been hiding inside businesses. “They were reluctant to come out,” he said. “They were horrified.”
Dozens of people were wounded and rushed to hospitals.
One of the doctors who treated victims, Dr. Jeremy Smiley, testified on Wednesday that he had abruptly fled the parade scene with his extended family. Once they were able to drive away, he asked his wife to drop him off at a nearby hospital where he works.
One of the victims in the emergency department was Cooper Roberts, an 8-year-old boy who was shot at the parade. He survived but was left paralyzed.
“There’s not a day goes by that I don’t think about Cooper,” Dr. Smiley said. “That will never leave me. There are things I’ll carry forever.”
Mr. Crimo’s trial was about to begin last month when he decided to change his plea on the morning of the trial. That plea brought some measure of consolation to many of the victims’ families, who were spared the ordeal of a trial that was expected to stretch several weeks.
“He received nothing in exchange for this plea today,” Eric Rinehart, the Lake County state’s attorney, said in March when the change of plea was announced. “We have been working for years to prepare our evidence.”
The parade is one of Highland Park’s most popular traditions, attended by thousands of people who line picturesque downtown streets, along restaurants and boutiques.
On the first Fourth of July after the mass shooting, Highland Park opted not to hold its usual parade, instead hosting a community walk and memorial ceremony.
Mr. Crimo’s father, Robert Crimo Jr., did not attend the hearing on Wednesday. He sponsored his son’s application for a state gun ownership permit, a step that was required for his son to receive the permit because Mr. Crimo was 19 at the time.
He pleaded guilty in 2023 to seven misdemeanor counts of reckless conduct for his role in helping his son own firearms.
