The parents of a man with mental illness who in April escaped from a hospital, then lunged at and was shot dead by police, are suing for what they say was a failure of the system to protect their son.

“They tell us all the time, if you follow the system that’s how you get good results,” said Kimberly Nicole Fussell, mother of Darryl Fussell, who was killed earlier this year. “Our son is dead, and we followed the rules.”

His parents held a press conference in Atlanta with their lawyers on Tuesday, one day after filing a lawsuit against several health care companies. Back in April, Fussell’s parents say they took the 23-year-old college student to the hospital, where he was diagnosed as a schizophrenic for the first time. He was then involuntarily committed for a psychiatric admission to Riverwoods Behavioral Health, according to the lawsuit.

“We never imagined that we would be up here, telling everybody about our son in the past tense,” said Darryl’s father, who is also named Darryl Fussell.

Two days later, Fussell was found non-responsive at Riverwoods with stable vital signs. He was taken to Southern Regional Medical Center, but Riverwoods Behavioral Health staff allegedly failed to tell the medical center that Fussell was an involuntary psychiatric patient. Fussell was potentially suicidal and homicidal, the lawsuit says, and at risk for trying to escape.

The lawsuit alleges that only after speaking with his parents, did Southern Regional Medical Center learn that Fussell was involuntarily committed to Riverwoods and at risk for self-harm and harm to others. They later assigned a person to monitor him, but Fussell was able to walk down four flights of stairs and leave the facility. The complaint alleges that hospital security was never notified, and a hospital lockdown never initiated.

During this time, Fussell wandered into a construction site. He took a hammer and began hitting himself in the head before laying down, according to the complaint. Construction workers called local police, and when officers spoke to Fussell several times, he did not respond. One officer then said “hey green shirt,” and Fussell allegedly grabbed a pair of scissors and lunged toward the officers. One officer then shot Fussell nine times.

The bodycam video from this incident has yet to be released. The Georgia Bureau of Investigation has conducted an investigation into the officer shooting, and that report was given to the DA’s Office Sept. 13th for review, according to a GBI spokesperson.

“Our heartfelt thoughts and prayers are with the family impacted by this tragic event,” said a statement issued by Southern Regional Medical Center. “Due to patient privacy laws and HIPAA, we are unable to discuss the care and treatment of a specific patient. Southern Regional Medical Center denies all allegations, and because this matter is now in litigation, we cannot make additional comments.”

Riverwoods Behavioral Health did not immediately respond to a request for comment.

“He was just suffering. What happened did not have to happen. They were supposed to take care of him. They were supposed to watch out for him, they were supposed to make him better,” said Fussell’s father. “But he just kept falling through the cracks.”

Fussell’s mom said she never wants another mother to experience her pain, and that mental illness “is real, and it’s okay. We don’t need to treat it like a poison.”

“Why didn’t they treat him like a patient who needed help?” she said. “Why did they treat him like a dog in the street?”

This is the second recent lawsuit in the news against Southern Regional Medical Center. The parents of a baby boy whom they say was decapitated during his delivery announced in August that they were suing Southern Regional Medical Center and others for negligence and allege that there were attempts to cover up details of the tragic death.