Detectives arrested 27-year-old Keith Haynes on a capital murder charge Wednesday.
Haynes had initially been questioned by police soon after Walker’s body was found. On his drive to the police department, Haynes posted a profanity-laced video to Facebook in which he denies any involvement and said he was going to “clear his name.”
Haynes and Walker had an ongoing relationship and had known each other since high school, police said.
Walker was found fatally shot in her bed in her town home in the 2200 block of Ridge Run Road.
Family members also have confirmed that Walker was seven months pregnant.
The victim’s 8-year-old son told detectives a man he knew as “Moosie” had been with his mother the night she was killed.
Haynes told police that was his nickname.
Police also said the investigation revealed Haynes had deleted text messages on his cell phone between he and the victim before allowing investigators to examine it.
A friend told police Walker had sent her screenshots of text messages from Haynes and said as recently as March 30 that she believed Haynes was trying to kill her.
“If I ever come up dead please show the police this and the other screenshots,” she told the friend, according to the arrest warrant.
Walker did not explain why she was worried, police said.
Haynes is being held on a $250,000 bond.
Haynes worked as a civilian employee at the Dallas County Sheriff’s Office.
According to records, he was hired as a detention service officer in 2013 and resigned a month later due to a family emergency. He was re-hired by DCSO in September 2015. In November, he was voluntarily demoted to courtesy patrol. Those are the people who assist drivers on the highway when they get a flat tire or break down.
“Due to the severity of the charges against him, we have initiated administrative proceedings concerning his employment here,” according to Dallas County Sheriff’s Office spokesperson Melinda Urbina.