Highland Park was devastated by the shooting that erupted on July 4, 2022. According to prosecutors, the accused gunman, then 21 years old, climbed onto the rooftop of a business in Highland Park’s idyllic downtown, where residents had lined the streets for the summertime parade. After he fired at paradegoers from above, he escaped by blending into the crowd, the authorities said.

He was arrested hours later in a nearby town after his car was spotted.

Killed in the shooting were Katherine Goldstein, 64; Irina and Kevin McCarthy, 35 and 37, a couple who left behind a toddler son; Stephen Straus, 88, a financial adviser; Ms. Sundheim, 63, an employee of a local synagogue; Nicolas Toledo-Zaragoza, 78, who had recently moved back to Highland Park from Mexico; and Eduardo Uvaldo, 69, a grandfather and bowling champion.

The elder Mr. Crimo faced intense scrutiny and criminal charges for his own role in the shooting. Prosecutors said that he had ignored obvious signs that his son was capable of violence — the younger Mr. Crimo once promised to “kill everyone” in the family home, prosecutors said, had expressed interest in committing a mass shooting in an exchange with a camp counselor and later sent text messages suggesting that he wanted to end his own life.

Mr. Crimo sponsored his son’s application for a state gun ownership permit, a step that was required for his son to receive the permit because of his age, 19 at the time. The father pleaded guilty in 2023 to seven misdemeanor counts of reckless conduct.

In 2023, on the first anniversary of the attack, officials in Highland Park decided not to hold a traditional parade. Instead, the city honored the holiday and the anniversary with a memorial ceremony, a community walk, a picnic and a concert.