How Billy Chemirmir Exploited Senior Living Communities and Killed 22 People

In March 2018, Mary Annis Bartel heard someone knocking at her apartment in Plano, Texas. When Bartel opened the door, the 91-year-old came face to face with a tall stranger wearing green rubber gloves—and she knew right away she was in danger.

The man told her not to fight back. He forced her onto her bed, then grabbed a pillow and pressed it down over her head and chest. Bartel lost consciousness.

Fortunately, Bartel’s friends discovered her before it was too late. However, the intruder had slipped away, making off with Bartel’s diamond rings and other pieces of jewelry.

At first, police were skeptical of Bartel’s story, but they eventually took her seriously. As their investigation continued, a far more sinister picture began to emerge, one that pointed to a methodical, calculated killer who had been targeting some of the community’s most vulnerable residents.

It turned out that a man named Billy Chemirmir was the stranger who attacked Bartel along with numerous other individuals in the Dallas metropolitan area. Bartel survived, but many of Chemirmir’s victims did not, including Lu Thi Harris, an 81-year-old woman police found dead in her apartment shortly after they arrested Chemirmir.

In the end, police believe Chemirmir killed at least 22 people—possibly more—between May 2016 and March 2018. Most of his victims were older women who lived alone in independent living communities for seniors. They suspect Chemirmir posed as a maintenance worker or caregiver, entered their homes, smothered his victims to death then stole their jewelry.

Tristin Engels, a licensed clinical forensic psychologist who co-hosts the Serial Killers & Murderous Minds podcast, tells A&E Crime + Investigation that Chemirmir exhibited high levels of “predatory intelligence.” Not only did he disguise himself in such a way that allowed him to gain access to vulnerable victims, but he also used a quiet and practical method that didn't alert anyone at the time of the incidents and made the deaths appear natural once the bodies were later discovered.

“That mixture of access, method, concealment and financial gain is not the behavior of an impulsive or opportunistic criminal,” Engels says. “It's calculated, disciplined and sustained.”

Much of Chemirmir’s background remains a mystery. However, he told the Dallas Morning News he was born and raised in Kenya, the son of a wealthy farmer with three wives. Chemirmir was one of the family’s 28 children.

When he moved to the United States in 2003, Chemirmir sold cars and worked as a senior caregiver, a career he’d discovered while taking care of his 100-year-old father back home. After initially finding clients through health care agencies, he decided to go out on his own and began charging $20 or $30 an hour to provide in-home care.

He got married in 2004, then divorced two years later. At some point, he became a legal permanent resident.

Before being arrested and charged with murder, Chemirmir had had a handful of brushes with the law. He was arrested twice for drunk driving, once for family violence and once for trespassing at a senior living complex, where police later determined he had likely killed two women.

It’s not clear when Chemirmir first began smothering and stealing from older women, nor how many people he killed. Though family members raised concerns about unusual circumstances and reported missing items, many of his suspected victims were initially ruled to have died of natural causes—primarily, strokes and heart attacks.

“The mentality of it was, ‘They were old, and they just died,’” Shannon Dion, whose 92-year-old mother Doris Gleason was among those believed to have been killed by Chemirmir, told AARP The Magazine in 2022.

Sunny Slaughter, a criminal behavior analyst, law enforcement instructor and litigation consultant, echoes that sentiment, adding that the case exemplifies how much society undervalues older adults.

“If these victims had been younger, healthier or more socially connected, the pattern might have been recognized sooner,” Slaughter tells A&E Crime + Investigation.

The case also serves as a reminder that serial offenders “don’t always fit the narrative we expect.”

“Sometimes they're quiet, methodical, unassuming and hiding in plain sight,” she says, adding that this makes them “some of the most dangerous predators.”

And while stealing valuable jewelry may have initially driven Chemirmir to commit the crimes, Slaughter believes his motivations likely evolved over time. Eventually, he may even have killed his victims for the thrill of it.

“He had gotten away with it previously, and he enjoyed it,” she says. “The pattern shows a deeper predation.”

After Bartel survived her attack, police re-examined hundreds of deaths across the area. In the end, prosecutors charged Chemirmir with 22 murders—13 in Dallas County, and nine in neighboring Collin County. Chemirmir, however, maintained his innocence.

“I am not a killer,” Chemirmir told the Dallas Morning News. “I’m not at all what they’re saying I am. I am a very innocent person. I was not brought [up] that way. I was brought [up] in a good family. I didn’t have any problems all my life.”

In November 2021, he was tried for the murder of Harris. However, the jury deadlocked 11 to 1 and could not reach a unanimous verdict, resulting in a mistrial. Prosecutors retried Chemirmir in April 2022 and, this time, he was found guilty of murder and sentenced to life in prison without the possibility of parole. Prosecutors did not seek the death penalty.

Then, in October 2022, Chemirmir faced a second murder trial for the death of 87-year-old Mary Brooks. He was found guilty and given a second life sentence without parole. After securing the two convictions, prosecutors dismissed the remaining cases, a decision that disappointed some of the surviving family members.

In September 2023, Chemirmir was killed by his cellmate at the Coffield Unit prison in rural East Texas. Authorities didn’t release many details about the incident, but his attorney, Phillip Hayes, described Chemirmir’s death as “a horrible tragedy.”

“Nobody deserves to be killed at any point, especially when you are in a place you’re being held against your will,” Hayes told the Associated Press.

However, some of the family members of Chemirmir’s victims viewed his death differently.

“This man did not have a peaceful passing,” Dion said. “There’s some relief in feeling that he didn’t get off easily.”

Meanwhile, though Chemirmir was no longer a threat, many family members continued to fight for longer-lasting changes to prevent similar incidents in the future. They formed an advocacy group called Securing Our Seniors' Safety and testified at the Texas capitol in Austin, calling on state lawmakers to require increased safety measures at senior living facilities.

“Billy Chemirmir knocked on my mother’s door. He had stalked her, then murdered her and stole from her,” Loren Adair-Smith, whose mother Phyllis Payne was killed in May 2016, told lawmakers in April 2025. “My sweet, trusting mother never would have dreamed that a serial killer was roaming the halls as she trusted in the security the management had promised.”

She added, “We cannot stand the thought that anybody else experiences what our families have experienced.”

Their advocacy paid off. In 2025, Texas enacted new legislation requiring senior retirement communities with a minimum of 20 residential units and common amenities to keep residents information about criminal incidents and perform criminal history background checks on all employees.

“It’s really beyond comprehension that it happened,” Tan Parker, the Texas senator who sponsored the legislation, said. “By setting these standards, the bill [aims] to create a safer living environment for seniors while ensuring they’re informed about potential risks to their well-being.”