Four years ago, a woman with severe mental illness poured a pot of boiling water over Michael Sorenson as he sat in his wheelchair at a Bloomington group home, leaving him with burns covering 35 percent of his body.

This week the Minnesota Court of Appeals ruled that the group home operator cannot claim legal immunity under a 1967 state law and shield itself from more than $1 million in potential civil damages.

In a far-reaching decision, a three-judge appeals panel held that Sorenson, 63, can sue his former group home operator, Options Residential Inc. of Burnsville, for damages from injuries he suffered when a roommate with a history of aggression burned him so badly with the scalding water that he was hospitalized for two months and then had to move into a nursing home.

Attorneys say the decision will make it harder for group homes and other facilities that house or treat people with disabilities to insulate themselves from often-costly lawsuits in cases of neglect or abuse. The 1967 statute, known as the Minnesota Commitment and Treatment Act (CTA), established procedural safeguards and rights for people being committed by the courts as mentally ill; however, a provision of the law also gave facilities protections against civil or criminal liability when they made a “good faith” effort to provide care to committed individuals.

The decision has broad implications for the estimated 14,000 Minnesotans who live in four-bed group homes across the state. In many of these homes, people with physical and developmental disabilities live in close quarters with people with severe mental illnesses, which can create a chaotic and sometimes violent atmosphere, a 2015 Star Tribune investigation found. At times, residents lash out at each other and staff, turning these homes into battlegrounds.

“This means the least among us will have the right to a legal remedy if they are harmed in a group home,” said Donald McNeil, a Bloomington attorney who represents Sorenson. “And no provider should be allowed to hide behind an immunity defense to avoid accountability.”

Options Residential did not return multiple calls seeking comment.

In the past, facilities sometimes would claim broad immunity from legal action when maltreatment involved a person who was civilly committed under the 50-year-old state commitment law. Now, however, that could prove more difficult. The appeals panel concluded that immunity under the law is limited to claims arising from a person’s civil commitment, and does not extend to harm done to individuals like Sorenson who are not committed as mentally ill.

One likely consequence of the ruling is that group homes and other residential providers will be more reluctant to admit individuals with serious and persistent mental illnesses, knowing they can be held liable for misconduct, warned Roberta Opheim, state ombudsman for mental health and developmental disabilities. This could make it tougher for people to find housing at a time when many of the state’s 3,500 group homes are struggling with staffing shortages and a lack of capacity, Opheim said.

“The decision was the right one, because it puts providers on notice that they can’t neglect a client and then claim broad legal immunity,” Opheim said. “At the same time, it will interfere with their willingness to take on high-needs clients.”

Sorenson, speaking Tuesday from his bed at an Edina nursing home, said he pursued a lawsuit because he wants to protect others from having to suffer a similar ordeal.

In May 2013, a woman who was diagnosed with schizophrenia and had a history of aggressive conduct, including starting fires and throwing hot liquids on others, moved into Sorenson’s Bloomington group home. Tensions arose immediately. Sorenson, who has a traumatic brain injury from a 1973 motorcycle accident, teased the new resident about her body odor. The woman responded by breaking Sorenson’s eyeglasses and spraying Lysol, a chemical cleaner, in his eyes. Options staff twice called Bloomington police, but the woman was still allowed to stay at the home, according to court documents.

“Right away, I could tell that she was not stable,” Sorenson recalled.

Later, as residents of the group home were preparing for dinner, the woman took a pot of hot water from the stove and poured it over Sorenson’s head while he was in his wheelchair, burning his shoulders, chest and groin area. His brother, Doug Sorenson, said he vomited in the hallway of Hennepin County Medical Center (HCMC) after seeing his brother’s scarred body. “He was literally boiled alive,” McNeil said.

The Minnesota Department of Human Services, which regulates group homes, investigated the incident and found the facility was responsible for neglect.

Before the assault, Sorenson was regularly able to venture out into the community. Now, he is barely able to lift his limbs and spends most of the day confined to a bed and wheelchair at an Edina nursing home. Sorenson still has deep red scars, stretching from his shoulders to his legs, from the burns and the skin grafts. He is seeking more than $1 million in damages to cover his medical bills and other costs related to care for his burn injuries.

On Tuesday, Sorenson took a moment to celebrate the court decision by sharing a bottle of his favorite root beer with his attorney. “You know, I just hope that someone is held accountable,” he said, “because what happened to me should never happen to anyone again.”