He said that he restrained the eight individuals, including six children, one of whom is believed to be his own, and shot them each in the back of the head, KHOU reports. The victims have been identified as Dwayne Jackson, 50, his wife Valerie Jackson, 40, and children Nathaniel, 13, Dwayne, 10, Honesty, 11, Caleb, 9, Trinity, 7, and Jonah, 6.
"We do not – cannot – fully comprehend the motivation of an individual that would take the lives of so many innocent people. Especially the lives of the youngest," said Chief Deputy Tim Cannon of the Harris County Sheriff's Office.
He added: "The killer's motives appear to be related to a dispute with Valerie, who was a former domestic partner."
A History of ViolenceConley, 48, has a history of criminal complaints against him dating back more than two decades, including various incidents of family violence, drugs and driving while under the influence, according to KHOU.
Last month, he was charged with assaulting a family member after he allegedly pushed his girlfriend's head against a refrigerator over and over, court documents obtained by KHOU show.
Conley had allegedly told the girlfriend to punish her 10-year-old son for coming home after dark. When she refused, he grabbed a belt, intending to discipline the boy himself, but she stopped him, prompting Conley to allegedly attack her instead.
On Sunday afternoon, Conley was charged with three counts of capital murder and denied bail, CBS News reports. He was arrested on Saturday after deputies were summoned to perform a welfare check on the home where the eight bodies were found that night.
Authorities did not comment on what led to the welfare check, but when they arrived they saw the body of a juvenile through a window, so they forced their way into the home. Conley began firing at them, prompting deputies to pull back. He surrendered an hour later.
Conley is believed to have been the father of 13-year-old Nathaniel. Police said that Conley and Valerie had recently rekindled their relationship, but when that soured, he ended up attacking her and her family.
He has not yet entered a plea to the charges.
'He's the Devil'A woman claiming to be the estranged wife of Conley spoke out on Sunday, telling KPRC that he's "the devil."
"I hope he is listening," Vernessa Conley said. "He's the devil. He was very abusive towards me. He would beat me up every day."
She added: "He almost broke my arm. I have a scar on my inner lip. He would pull my hair. He would beat me not in my face because he would always tell me, 'I don't want anyone to see.' I was pregnant with my daughter and he would threaten me. He would threaten to kill me and the baby."
Conley and Vernessa had one daughter together. She too spoke to KPRC, condemning her father's brutal actions.
"You could have let the kids go," said Quatasha Conley of her father.
"You didn't have to kill the kids."
Want to keep up with the latest crime coverage? Click here to get breaking crime news, ongoing trial coverage and details of intriguing unsolved cases in the True Crime Newsletter.