Billy Chemirmir: The North Texas Serial Murder Case
Overview
Billy Kipkorir Chemirmir was a Kenyan-born convicted murderer and suspected serial killer whose crimes centered on elderly residents of the Dallas-Fort Worth area of Texas. Between 2016 and 2018, prosecutors and investigators linked him to a remarkable series of deaths in senior-living communities and private homes. Chemirmir was eventually indicted for 22 murders and convicted of two: the murders of Lu Thi Harris and Mary Brooks. Authorities alleged that his primary motive was robbery and that he deliberately selected older victims whose deaths might initially appear natural.
The investigation revealed an especially disturbing pattern. Many of the victims were elderly women living alone, either in apartments inside retirement communities or in private residences. Prosecutors alleged that Chemirmir frequently entered senior communities while pretending to be a maintenance worker, caregiver, or other person who had a legitimate reason to be there. In other cases, investigators believed he watched elderly women while they were shopping and followed them home.
Once alone with a victim, Chemirmir was accused of using pillows or his hands to suffocate or smother them before stealing jewelry, watches, cash, and other valuables. Because suffocation can leave relatively little obvious external trauma, and because the victims were elderly, a number of deaths were initially attributed to natural causes. Only after Chemirmir was identified following a survivor's attack did investigators begin looking backward at suspicious deaths throughout North Texas.
The Early Pattern at Senior-Living Communities
Some of the earliest deaths later associated with Chemirmir occurred at Edgemere, a senior-living community in Dallas. Phyllis Payne and Phoebe Perry died there only weeks apart in 2016. Investigators later alleged that Chemirmir killed both women and stole property from their apartments. Another Edgemere resident, Dr. Catherine Probst Sinclair, had died under suspicious circumstances shortly before them and was subsequently considered a possible additional victim.
Chemirmir also appeared at Edgemere when he had no legitimate reason to be inside the facility. He was confronted and eventually arrested for criminal trespassing. After his release, investigators believe his activity shifted to The Tradition-Prestonwood, another retirement community in Dallas. During the summer and fall of 2016, a succession of residents died there and valuables disappeared from their apartments.
Family members sometimes noticed details that did not fit a peaceful natural death. Wedding rings, necklaces, jewelry boxes, watches, and other personal possessions were suddenly missing. Nevertheless, because there were often no immediately obvious signs of violence, many of the deaths were not originally treated as homicides. Years later, those observations by relatives became important pieces of a much larger investigation.
The Breakthrough
The investigation finally changed direction in March 2018 after 91-year-old Mary Bartel survived an attack at Preston Place in Plano. Bartel reported that a man forced his way into her apartment, ordered her toward her bed, and placed a pillow over her face. She lost consciousness but survived and was able to give police information about her attacker.
Investigators were already examining suspicious-person reports involving senior communities. Information from Bartel's attack, together with descriptions of a vehicle seen around the complexes, directed police toward Chemirmir. On March 20, 2018, officers watching him saw him discard items into a dumpster near his apartment. Among the discarded property was a jewelry box connected to 81-year-old Lu Thi Harris.
Police went to Harris's Dallas home and found her dead. Additional property belonging to Harris was associated with Chemirmir, and he was charged with her capital murder. The discovery provided investigators with the link they needed to reexamine years of deaths that had previously been classified as natural or accidental.
Victims Named in Murder Indictments
Chemirmir was ultimately indicted in connection with 22 deaths. Only two of those murder cases resulted in convictions before his death. The remaining names are therefore listed as victims in cases in which prosecutors formally accused Chemirmir of murder rather than as murders proven individually at trial.
- Phyllis Payne, 91 — May 14, 2016 — Edgemere senior-living community, Dallas, Texas. Payne's death was originally treated as natural. Investigators later alleged that Chemirmir killed her and stole jewelry and other property.
- Phoebe Perry, 94 — June 5, 2016 — Edgemere, Dallas, Texas. Perry was another Edgemere resident whose death was later included among the murders attributed to Chemirmir.
- Joyce Abramowitz, 82 — July 20, 2016 — The Tradition-Prestonwood, Dallas, Texas. Her obituary records July 20 as her date of death, although the criminal case used an alleged offense date of approximately July 18. Family members subsequently reported property missing from her apartment.
- Juanita Purdy, 82 — July 31, 2016 — The Tradition-Prestonwood, Dallas, Texas. After her death, relatives discovered that jewelry had disappeared from her residence.
- Leah Corken, 83 — August 19, 2016 — The Tradition-Prestonwood, Dallas, Texas. Her death was initially considered natural, but missing jewelry and the later investigation caused authorities to reconsider the circumstances.
- Margaret White, 86 — August 28, 2016 — The Tradition-Prestonwood, Dallas, Texas. White died only days after Corken, adding another death to what investigators later viewed as a concentrated series at the same facility.
- Norma French, 85 — October 8, 2016 — The Tradition-Prestonwood, Dallas, Texas. French was known for wearing her wedding ring, but it was missing after her death. Chemirmir was later indicted for her murder.
- Glenna Day, 87 — October 15, 2016 — The Tradition-Prestonwood, Dallas, Texas. Her death was initially attributed to natural causes. A Dallas County grand jury later indicted Chemirmir for killing her.
- Doris Gleason, 92 — October 30, 2016 — The Tradition-Prestonwood, Dallas, Texas. Her daughter found her dead in her apartment and discovered that important pieces of jewelry were missing. Court records used an alleged offense date around October 29, while family accounts place the discovery of her death on October 30.
- Helen Lee, 82 — September 2, 2017 — Parkview senior community, Frisco, Texas. A Collin County grand jury indicted Chemirmir for her capital murder in 2022, alleging that she was smothered during a robbery or burglary.
- Marilyn Bixler, 90 — September 17, 2017 — Parkview, Frisco, Texas. Bixler's death became the inspiration for legislation known as Marilyn's Law, intended to ensure that relatives are notified when a medical examiner changes information concerning a person's cause of death.
- Minnie Campbell, 84 — October 31, 2017 — Preston Place Retirement Community, Plano, Texas. Campbell's death was one of several suspicious deaths at Preston Place later incorporated into the Chemirmir prosecution.
- Diane Delahunty, 79 — December 3, 2017 — Preston Place, Plano, Texas. Her family found that several rings were missing after her death. Chemirmir was formally indicted for her murder in 2022.
- Mamie Dell Miya, 93 — December 8, 2017 — Preston Place, Plano, Texas. A Collin County indictment alleged that Chemirmir intentionally caused Miya's death by smothering her while committing or attempting to commit robbery or burglary.
- Doris Wasserman, 90 — December 23, 2017 — The Tradition-Prestonwood, Dallas, Texas. Wasserman had been with family earlier that day and was later discovered dead in her apartment. Her death was subsequently attributed to Chemirmir by investigators and prosecutors.
- Carolyn MacPhee, 81 — December 31, 2017 — private residence, Plano, Texas. MacPhee died in her home and was missing her wedding ring. Evidence developed after Chemirmir's arrest contributed to authorities treating her death as a homicide.
- Rosemary Curtis, 76 — January 19, 2018 — private residence, Dallas, Texas. Her published obituary confirms January 19 as her date of death. She was later included among the women Chemirmir was accused of killing and robbing.
- Mary Brooks, 87 — January 31, 2018 — Richardson, Texas. Prosecutors presented evidence that Chemirmir encountered Brooks while she was shopping, followed her home, killed her, and took jewelry. He was convicted of her capital murder in October 2022.
- Martha Williams, 80 — March 4, 2018 — Preston Place, Plano, Texas. Williams was one of several Preston Place residents who died during the weeks immediately preceding Chemirmir's arrest.
- Miriam Nelson, 81 — March 9, 2018 — Preston Place, Plano, Texas. Shortly before her death, Nelson had reported that a man claiming to be checking for leaks entered her apartment. Jewelry was discovered missing after she died.
- Ann Conklin, 82 — March 18, 2018 — Preston Place, Plano, Texas. Conklin died only one day before the attack on Mary Bartel that finally helped investigators identify Chemirmir.
- Lu Thi Harris, 81 — March 20, 2018 — private residence, Dallas, Texas. Police traced a jewelry box discarded by Chemirmir to Harris and found her dead inside her home. Her case produced Chemirmir's first murder conviction.
Additional Suspected Victims
Investigators and families believed the 22 indictments might not represent the complete scope of Chemirmir's crimes. Other deaths were publicly investigated or alleged in civil litigation but did not result in murder convictions against him.
- Dr. Catherine Probst Sinclair, 87 — April 8, 2016 — Edgemere, Dallas, Texas. Sinclair was found dead in her apartment and a safe containing valuables was reportedly missing. Her death was later treated as suspicious and her family publicly identified Chemirmir as the person they believed was responsible.
- Solomon Spring, 89 — early October 2016 — The Tradition-Prestonwood, Dallas, Texas. Spring was the principal male victim publicly associated with the Chemirmir investigation. He was found badly injured in his apartment with valuables missing. His death was initially considered the result of a fall, but investigators later examined it as a possible Chemirmir homicide.
- Unnamed 81-year-old woman — December 10, 2017 — Preston Place, Plano, Texas. Her death was identified in civil litigation and reporting surrounding the Preston Place investigation as another case believed to fit the pattern attributed to Chemirmir.
Women Who Survived Attacks
At least two women survived attacks that prosecutors attributed to Chemirmir. Their survival was critical because it provided investigators with information unavailable in the earlier cases.
- Kay Lawson, 93 — October 29, 2017 — Parkview, Frisco, Texas. Chemirmir was accused of knocking Lawson down and attempting to smother her with a pillow while stealing jewelry. She survived.
- Mary Bartel, 91 — March 19, 2018 — Preston Place, Plano, Texas. Bartel survived after being forced toward her bed and smothered with a pillow until she lost consciousness. Her description of the attacker and the subsequent police investigation directly contributed to Chemirmir's arrest.
Why the Crimes Went Undetected
One of the most significant aspects of the Chemirmir case was the length of time the deaths remained unrecognized as possible homicides. Many of the victims were in their seventies, eighties, or nineties, making an apparently sudden natural death seem plausible. When relatives noticed missing jewelry, the disappearances were sometimes considered separate property crimes instead of evidence that a robbery and killing had occurred together.
Several families later argued that stronger security, more careful death-scene investigations, and better communication between senior facilities and police might have exposed the pattern sooner. Chemirmir was able to move between Dallas, Plano, Frisco, and Richardson, meaning individual incidents were also divided among different police departments and counties.
The later investigation forced authorities to revisit numerous unattended deaths. In several cases there was little physical evidence left to examine because bodies had already been buried or cremated and apartments had been cleaned. This was one reason that prosecutors relied heavily on circumstantial evidence such as stolen jewelry, phone-location information, surveillance recordings, vehicle sightings, witness testimony, and similarities between the attacks.
The Murder of Lu Thi Harris and First Conviction
Lu Thi Harris's murder became the central case against Chemirmir. Prosecutors argued that he had selected Harris as a target, followed her home, smothered her, and robbed her. When police investigating the attack on Mary Bartel began following Chemirmir, they saw him discard a jewelry box bearing Harris's name. Police went to her residence and discovered her body.
Chemirmir first went to trial for Harris's murder in November 2021. That proceeding ended in a mistrial after the jury was unable to reach a unanimous verdict. Prosecutors immediately announced that they would try the case again.
The retrial began in April 2022. On April 28, a Dallas County jury convicted Chemirmir of capital murder after approximately 45 minutes of deliberation. Because prosecutors were not seeking the death penalty, the conviction carried an automatic sentence of life imprisonment without the possibility of parole.
The Murder of Mary Brooks and Second Conviction
Prosecutors next tried Chemirmir for the death of Mary Brooks. Surveillance footage from a Walmart became an important part of the case. The prosecution argued that Chemirmir watched Brooks at the store, followed her after she left, and then entered her Richardson residence.
Brooks was later found dead, and jewelry was missing. Investigators initially believed that her death was natural, but the circumstances were reconsidered after Chemirmir's arrest. Prosecutors used surveillance evidence, telephone information, evidence about his vehicle, and similarities to other attacks to construct their case.
On October 7, 2022, a Dallas County jury found Chemirmir guilty of Brooks's capital murder. He received a second sentence of life imprisonment without parole. The two convictions guaranteed that he would spend the remainder of his life in prison even though most of the other alleged murders would never be tried before a jury.
Death in Prison
Chemirmir was imprisoned at the Coffield Unit near Tennessee Colony, Texas. On September 19, 2023, prison officials announced that the 50-year-old Chemirmir had been killed by his cellmate. At the time of his death, he was serving two life sentences without the possibility of parole.
His death meant there could be no future trials determining his legal responsibility for the remaining murders. For families whose relatives were included among the other indictments or suspected cases, the unanswered questions therefore remained permanent. Although prosecutors had established beyond a reasonable doubt that Chemirmir murdered Lu Thi Harris and Mary Brooks, the complete number of people he killed can no longer be determined through criminal trials.
Legacy of the Investigation
The Chemirmir case became one of the most significant elder-homicide investigations in Texas history. It demonstrated how a killer could exploit assumptions surrounding elderly deaths, particularly when the victim lived alone and showed few obvious signs of violence. It also exposed the difficulty of recognizing a serial pattern when deaths occur across different facilities and police jurisdictions.
Families of the victims became outspoken advocates for stronger security in senior communities and more careful investigations of unexpected deaths. The controversy also contributed to legislative changes concerning notification of families when official conclusions about a death are altered.
Billy Chemirmir was convicted of murdering two women, formally accused through indictments of killing 20 others, and investigated in connection with still more suspicious deaths. The cases stretched from Dallas senior-living communities to private homes in Plano and Richardson and involved victims whose ages and circumstances made them especially vulnerable. While the full extent of his crimes remains uncertain, the investigation established a pattern of elderly people dying under seemingly ordinary circumstances while valuable possessions disappeared around them—a pattern that went unnoticed until a surviving victim gave police the opportunity to connect the cases.
