On July 16, 2012, the body of Mary Ann Murphy, 48, was found stabbed to death in bed in her family home in Humble, Texas.
It was a little after 1 a.m. when 911 received a frantic call from Mary Ann’s daughter, Keri. She told them that someone had kicked in the back door, and after she heard her mother scream, she ran out of the house.
The stab wounds were extensive — and plenty. She had been stabbed more than 70 times.
“On her legs, on her arms, hands, neck, in the face. It was obvious that it was a very brutal attack,” said Craig Clopton, former investigator at the Harris County Sheriff’s Office, in the latest episode of “Killer Couples,” airing Sundays on Oxygen 7/6c.
A murder investigation into the violent attack on Murphy, who was sleeping at the time, first pointed to Zein Ahmed, a classmate of Murphy’s daughter.
But all was not as it seemed.
The First Bloom Of Love
“Zein was a guy that she knew… that showed interest in her, that she wasn’t at all interested in him,” remembered Clopton, of Keri Murphy’s early days in high school. They became friends, and Keri continued to expand her social circle through choir.
But then she met an older girl — 19-year-old Rebecca Keller, a senior whose nickname was Bunny.
“Rebecca was three to four years older than Keri. They clicked immediately. It was an immediate draw towards each other,” recalled Keri’s brother Scott on “Killer Couples.”
Rebecca Keller and Keri fast became a couple.
“Keri Murphy and Rebecca Keller’s relationship was consuming to both of them, this may have been Keri Murphy’s first relationship with anyone in a romantic sense, and she fell head over heels,” said Anna Emmons, a prosecutor with Harris County, on “Killer Couples.”
The change in Keri’s behavior troubled her family.
“I had never seen Keri become completely and utterly infatuated with a single person,” said her brother Scott Murphy.
Investigators were suspicious because coagulated blood suggested that Keri might have waited a longer time to call the police than she first indicated.
“The timeline doesn't match. We know how long it took for the deputies to get there and go inside and find your mother,” said Clopton, giving insight into the investigation. “That would've been within minutes after you said you heard your mother's scream.”
A Classmate Named
Keri began to switch her story, and after taking a polygraph test, confessed that she knew who killed her mother. She named her classmate Zein.
She said he helped her because her mother Mary Ann did not appreciate the age difference between Keri and Rebecca.
“Mom could see the obsessions beginning and she didn’t feel that it needed to continue,” remembers Scott Murphy about their mother’s objections to the relationship on “Killer Couples.”
After Keri was grounded, she told investigators that she reached out to Zein for help.
“Keri had solicited him to come to the house and beat on the wall to scare the mom,” Clopton said of Keri’s first admission.
Ahmed confessed to the crime, perhaps fitting too neatly into the narrative.
But he got some key details wrong in his confession: He said he walked up a flight of stairs to get to Mary Ann’s room — and the Murphy residence was just one story.
His parents were insistent on his innocence and said they had proof he was playing video games on the night of the murder.
Ahmed told the Houston Chronicle his first priority upon getting out of jail was to “find work so he can repay his mother” who had sold all the gold jewelry from her homeland of Pakistan that had been in her family for generations.
So why had Ahmed confessed?
“He may not be of an education or maturity level to understand and comprehend everything that was going on,” said Emmons to the Houston Chronicle.
A Burner Phone
Investigators looked at Keri Murphy more closely, and discovered a motive when they found out that Mary Ann Murphy had banned Keri from speaking with her lover Rebecca after Keri’s father discovered them together in the house alone, according to brother Scott.
Rebecca apparently gave Keri a cell phone to communicate with her after the grounding.
“They called it the ‘bunny phone,’” said Clopton.
So why hadn’t Keri used that phone to call 911 instead of going to a neighbor’s house?
The investigators looked into phone records for that number and found that they had texted a lot the night of the murder. That’s when Rebecca’s story changed.
“‘I went over there because Keri called me and said she had killed her mom,’” paraphrased Clopton, recalling how Rebecca’s story suddenly adapted.
Rebecca told investigators that Keri came up with the idea to “blame it on Zein,” according to Clopton.
They looked at the internet history on Keri’s burner phone.
“Keri was googling ‘what's the quickest way to kill somebody?’” recalled Clopton. “Those Google searches were at the same time she's talking on the phone with Rebecca. So I know that they are scheming this together.”
“They wanted to be together, and Mary Ann stood in the way,” explained Emmons on “Killer Couples.”
A Crucial Misstep
The truth would soon come out: The girls would continue to talk while they awaited trial, perhaps not knowing that their phone calls were recorded. Their conversations indicated that Rebecca had done the stabbing, not Keri.
The prosecution’s case illustrated a timeline of events: Mary Ann had discovered their burner phone, which contained evidence of sexting that could have been used against Rebecca, as Keri was still a minor. The Texas age of consent is 17.
"This was a cold-hearted execution… [Keri] planned this out,” said prosecutor Emmons to the Houston Chronicle.
It is why Keri Murphy was tried as an adult, though still 16, according to St. Louis local station KMOV4.
It appears that Keri and Rebecca, though no longer together as a couple, are still friends and in touch with one another.
Watch this and more horrifying tales of love affairs turned violent in “Killer Couples” on Oxygen, Sundays 7/6c.
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