WAUKEGAN, Ill. (AP) — Survivors and relatives of people killed in a 2022 mass shooting at an Independence Day parade in suburban Chicago are set to address the gunman Wednesday at his sentencing hearing.

Robert E. Crimo III, 24, pleaded guilty last month to the shooting that left seven people dead and dozens more injured. His plea change, just moments before opening statements at his trial, came as a shock even after years of unpredictable legal proceedings.

Crimo is certain to spend the rest of his life in prison. Each count of first-degree murder carries a maximum natural life sentence in Illinois. Prosecutors and attorneys for survivors say addressing Crimo is an important step.

“They have been patiently waiting for justice to be served,” said a statement from Romanucci & Blandin, a Chicago-based law firm that represents nearly 50 victims. They “will tell their personal stories to the court, and they are steadfastly committed to pursuing justice.”

Attorneys were unsure how many people might give so-called “victim impact statements,” saying some may decide at the last minute. Prosecutors are also expected to lay out evidence during the sentencing hearing at the Lake County Courthouse, roughly 45 miles (70 kilometers) from Chicago.

The case has moved slowly through the court, in part because of Crimo’s erratic behavior.

He was expected to accept a plea deal last year but changed his mind once he got to court, shocking even his own attorneys.

Crimo fired his public defenders and said he would represent himself. Then he reversed his decision. He’s refused to leave his cell to attend court proceedings at times, including during parts of jury selection. After he pleaded guilty in court, he signed documents waiving his right to trial with both his own name and the name “Donald Trump.”

Ashbey Beasley attended the parade with her son in 2022. Though they weren’t injured, she said they had to run for their lives and seeing Crimo adds to their trauma.

“Every single time I see him, it’s stressful,” she told reporters after the guilty plea. “It’s upsetting for everyone in our community.”

Dozens were wounded in the shooting in the suburb about 30 miles (50 kilometers) north of Chicago. They ranged in age from their 80s down to an 8-year-old boy who was left partially paralyzed.

Authorities said Crimo perched on a roof and fired into the crowds. Witnesses described confusion as the shots began, followed by terror as families bolted from the downtown parade route, leaving lawn chairs and strollers behind.

Prosecutors had reams of evidence, including Crimo’s videotaped confession to police.

“We were 1,000% ready to go to trial and prove him guilty to the jury. We have been working for years to prepare our evidence,” Lake County State’s Attorney Eric Rinehart told reporters after the guilty plea.

Prosecutors initially charged Crimo with 21 counts of first-degree murder — three counts for each person killed — and 48 counts of attempted murder for the injured. Prosecutors later dropped 48 less serious counts of aggravated battery before jury selection.

Residents in the upscale Highland Park community of roughly 30,000 have mourned the shooting deeply. Some potential jurors were excused because of their connections to the high-profile case. Several survivors have also filed lawsuits against Crimo and gunmaker Smith & Wesson.

City leaders canceled the usual parade in 2023, opting instead for a “community walk.” The parade was reinstated last year on a different route and included a memorial.

The seven people killed in the shooting were Katherine Goldstein, 64; Jacquelyn Sundheim, 63; Stephen Straus, 88; Nicolas Toledo-Zaragoza, 78; Eduardo Uvaldo, 69; and married couple Kevin McCarthy, 37, and Irina McCarthy, 35.

Crimo’s father, Robert Crimo Jr., a former mayoral candidate, was charged in connection with how his son obtained a gun license. He pleaded guilty in 2023 to seven misdemeanor counts of reckless conduct. He served less than two months in jail.