(CNN) - Brenda Bennett-Johnson and Rosie Brooks said they thought they were looking at their badly beaten brother in a hospital bed. He was breathing only with the help of a ventilator.
The sisters had gotten a call from a social worker that a man on life support at Chicago's Mercy Hospital and Medical Center was believed to be their brother Alfonso. The sisters told CNN affiliate WBBM they didn't speak with Alfonso much.
"(The social worker) was looking for relatives of Alfonso Bennett," Brooks told the affiliate. "I told her that was my brother. And she said, 'Well, he's here in ICU.'"
The caller told them their brother had been badly beaten, especially his face, the sisters said.
Except the man wasn't their brother.
How the man got to the hospital
Chicago police spokesman Anthony Guglielmi told CNN that on April 29, police found the man badly beaten. WBBM reports he had no clothes and no identification.
Guglielmi says witnesses told police the man's name was Elijah Bennett. The man was taken to the hospital and put on life support for a week.
Because no family members came to claim him, Guglielmi said, the hospital called police for help identifying him.
"The name Elijah Bennett showed no match on the database," Guglielmi said. "The other person that comes up is Alfonso Bennett. So the officer gave the picture to the hospital so they could make a positive ID with the family."
After that is when Brooks says she got the phone call from the social worker.
How the man got taken off life support
When the sisters went to the hospital, they said, they didn't recognize the man in the bed as their brother.
"They kept saying CPD (Chicago Police Department) identified this person as our brother," Bennett-Johnson told WBBM.
She said the nurse told her police had identified him through mugshots, but that budget cuts prevented them from making an ID.
The man's health was deteriorating and the family faced a difficult decision about whether to stop life support. They told WBBM they believed they had to decide whether or not to take their brother off life support.
So they signed legal documents stating the man was their relative. The ventilator was removed and the man died shortly afterward.
The brother reappears
The sisters began making funeral arrangements, even purchasing a casket.
But the planning came to an abrupt stop when Alfonso walked through another sister's front door.
"'Brenda! Brenda! It's Alfonso! It's Alfonso,'" Bennett-Johnson said to WBBM, recounting what her sister said on the phone. "I could have almost had a heart attack."
They very quickly realized the grim mistake that was made. The sisters had approved removing life support for a stranger.
"It's sad that it happened like that," Bennett-Johnson told WBBM. "We made all kinds of decisions on someone that wasn't our family."
The sisters said police later identified the man at the morgue through fingerprints. The sisters told WBBM that police are now looking for his family.
"It is extremely troubling that this sort of thing happened," Cannon Lambert, the attorney for the sisters, told CNN. "There seems to be no protocol in place to prevent it from occurring going forward, which is even more frightening.
Investigation into the death and the mistake
When asked for comment, Chris Vicik, a spokeswoman for the hospital, told CNN the family identified the patient as their brother, but that privacy laws prevent them from sharing further details.
CNN has asked the hospital whether it followed its policies on identifying John Doe patients and whether the case is under investigation, but has not yet received a response.
Chicago Police said it is looking into every aspect of this incident.
"To say that we currently have questions is an understatement," Guglielmi said on Twitter.
Speaking with CNN, Guglielmi said the department takes personal privacy very seriously and that there are other methods the police use to verify and check identity in hopes of finding a family member.
"If the family said he wasn't a relative, we would have done (the other methods)," he said.
In addition to confirming an administrative investigation into how the notification occurred, Guglielmi said there is an open criminal investigation by police into how the man died.
This is not the first time a person has allowed a patient to be removed from life support, wrongly believing the patient to be a family member.
In July 2018, Shirell Powell was told her brother was in a New York hospital, brain-dead after a narcotics overdose. She allowed him to be taken off life support and only later was told the man was not her brother.
Powell is suing the the hospital for negligence. The hospital told CNN earlier this year it did not believe her claim "has any merit."
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