The Chicago Park District is launching reform efforts after a lifeguard allegedly shot and killed a teen at Douglass Park earlier this year.

Charles Leto, 55, has been charged with first-degree murder and several other felonies in connection to the June 26 shooting, which left 15-year-old Marjay Dotson dead and 14-year-old Jeremy Herred critically injured.

Leto’s attorneys have argued that the shooting occurred in self-defense, but prosecutors allege that surveillance video and eyewitness testimony contradict those claims, laying out their case in court documents released earlier this month.

A review launched by the Park District used employee interviews, examined personnel files, emails and text messages, according to a press release. Though the review did not find indications Leto would commit an act of violence, there were “significant weaknesses” found in documenting employee conduct and in staff accountability.

The review found that while Leto had passed all mandatory background checks to work as a lifeguard, he also had been involved in several verbal altercations with staff and patrons during his time as an employee. Those were managed at the local level and were not formally documented or tracked in a central personnel system, according to the report.

As a result of the report’s findings, several new reforms are being put into place at Douglass Park, including the placement of a fixed-post security officer and an assessment of the park’s security camera system.

The district will also implement new training programs focused on de-escalation, mental health response, and active threat scenarios. The district is also updating its signage on the prohibition of firearms.

Prosecutors have revealed new details about the moments leading up to a Douglass Park shooting that left a 15-year-old dead and a lifeguard charged with murder.

Centralized tracking of verbal warnings, coaching and patron complaints will also be implemented, with supervisors receiving enhanced training, according to officials.

Chicago Park District Superintendent and CEO Carlos Ramirez-Rosa said that the review process was thorough and dedicated to preventing a similar act of violence from occurring again.

“This was a horrific and heartbreaking act of violence. Nothing can bring Marjay back or undo the pain caused to Jeremy and their families, but we must act with urgency and integrity to ensure a tragedy like this never happens again,” he said in a statement. “Our internal review was guided by three principles: thoroughness, transparency, and accountability. We are sharing our findings with the families, the public, and our Board because our communities deserve to know the truth and see how we’re responding.”

According to the proffer released by prosecutors in the case, the June incident began when unknown individuals moved a bike belonging to the defendant in the case. At least one teen is believed to have entered the pool area through an employee door after being denied entry into the pool without an adult guardian.

After the pool closed at 7 p.m., the defendant retrieved his bike from the top of a staircase and got into a verbal altercation with a 15-year-old boy. Eyewitnesses told police that the altercation was non-physical in nature, and lasted between 30 and 45 seconds.

Leto then allegedly walked his bike up the sidewalk, flipped it upside down, took off a backpack and began rummaging through it, surveillance video showed. The three teens in the incident were then seen on video walking down the sidewalk.

As they approached the defendant in the case, eyewitnesses told police that they were walking past him, with no threats made in the lead-up to the final confrontation.

The lifeguard, Charles Leto, 55, of Lakeview, was charged with murder and attempted murder in the slaying of 15-year-old Marjay Dotson and the wounding of 14-year-old Jeremy Herred outside the Douglass Park pool. Leto also shot at a third teenager but did not wound him, authorities say.

The 15-year-old who had previously gotten into an argument with the defendant then reached toward the bike, prosecutors said. It was at that moment that Leto allegedly stood up and aimed his pistol at Dotson, firing once and striking him in the back as he tried to turn away from him.

Leto then allegedly fired the gun at Herred, striking him in the neck. He fired again at the third victim, who was not hit by gunfire.

Herred was rushed to an area hospital, with prosecutors detailing the extent of his injuries. It is believed that the gunshot shattered a vertebrae in his neck, which then severed an artery. He remains hospitalized in critical condition.

After the shots were fired, Leto called police and said he had been attacked by the teens, and that he had acted in self-defense. He was taken into custody and taken to a local police station.

Prosecutors say that video evidence and eyewitness testimony both contradict his claims of self-defense, and Leto was charged with first-degree murder, attempted murder, aggravated discharge of a firearm and aggravated battery in the discharge of a firearm.

Defense attorneys have described Leto as a decorated Marine Corps veteran with no criminal history, and emphasized that he has a valid FOID card and a concealed carry permit.