Walker, 46, is charged with three counts of first-degree murder, three counts of armed criminal action, and first-degree burglary.
Bloody drag marks led police to Williams' body, which was found outside a home at 39th and Paseo around 8 a.m. Whoever killed him had attempted to hide his body under a tarp and a tire.
Inside the home, detectives found the bodies of the Pikes. All three victim had been shot, and .40-caliber shell casings were found near the victims' bodies.
Prosecutors say the last call to one of the victim's phones was from Walker, whose two-tone older model truck was seen in front of the residence the night before by a witness.
Witnesses told police that Walker regularly bought drugs from Herschel Pike at the home. After the killings, the witness saw Walker with a "gallon-sized Ziploc bag full of marijuana ... and more cash than he usually had." The witness told police that Walker had a history of robbing drug dealers.
Detectives also interviewed someone who claimed to be Herschel Pike's pot supplier, and admitted that their marijuana is delivered in gallon-sized plastic bags.
Court records say Walker sold a gun to an undercover officer. The gun was tested and found to have DNA from Donna Pike in the barrel. Records also say that shoe prints left at the crime scene matched those of Walker and one of his associates, who told police that Walker took him to the Pikes' home, where he saw Herschel Pike dead in a chair. Walker admitted killing the Pikes and Williams, the associate told police. Walker also told the associate that he shot Williams in the head when he came over to the home to see what was happening.
Cell-phone records showed that Walker's phone was in the area of the homicides late on January 15, records say.
In an interview with police, Walker denied committing the killings. He claimed that the gun used in the slayings had been planted on him by a third party.
Prosecutors are seeking a $250,000 cash bond for Walker, who is in federal custody.
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