Just before 2 p.m. on Friday, Nov. 14, 1997, Michigan police received a disturbing 911 call from a group of fishermen who were casting their lines in Flint River. They told authorities that as they were walking down a trail toward the water, they spotted what appeared to be a pile of blankets.
Looking underneath the bedding, however, they made a gruesome discovery — the bruised and bloodied body of nurse and local waitress Nancy Billiter.
When first responders arrived, they discovered Billiter had sustained multiple wounds to the head and face, and on her chest, there were large, circular dark spots, evidence of potential chemical or electrical burns.
While the comforter that Billiter was wrapped in had been doused in gasoline, the remains had not been set on fire, according to “Killer Couples,” airing Thursdays at 8/7c on Oxygen.
Hoping to learn more about the moments leading up to Billiter’s death, investigators interviewed her friend and roommate, Carol Giles, at her home, where Billiter had moved in after the death of Carol’s husband, Jesse Giles.
Jesse, a nearly 500-pound diabetic who struggled with multiple health issues following a stroke, passed away from a supposed heart attack in September 1997. That is when Billiter offered to move in to help her friend pick up the slack around the house and take care of Carol’s two children while she was at work.
Carol told investigators that the last time she had seen Billiter was earlier that week on Tuesday night, when Billiter came home from work. Carol claimed that she, her boyfriend, Tim Collier, and Billiter hung out until 1:30 a.m., when Billiter supposedly left to visit her mother, who lived nearby.
When questioned if she thought it was normal that Billiter had not returned to her house for several days, Carol’s demeanor shifted, and she became evasive.
Authorities asked Carol to continue the interview at the West Bloomfield Police Department, and she was transported to the local station, where she confessed that she had not been completely honest during their initial conversation.
Carol claimed that on the evening of Nov. 12, 1997, Collier got into an argument with Billiter about a burglary that had taken place while the couple was on a trip to California. The vacation was cut short, however, when Billiter, who was at home watching the kids, called them and said that the house had been broken into and some money was stolen.
Carol said Collier was suspicious of Billiter and believed that she had fabricated the break-in to cover up her own theft, and he later confronted her about the burglary. The argument quickly turned physical, and Collier pulled out a gun and began hitting Billiter, according to Carol.
Collier tied her up to a bed in the basement, continuing to beat and assault her, before he smothered her with a bleach-soaked towel. Carol said she watched in horror as Collier slowly suffocated her friend to death, and that Collier threatened to kill her if she told anyone about the murder.
Once Billiter was dead, Carol said Collier forced her to clean up the crime scene, later dumping the body in Flint. While Collier had planned to burn Billiter’s remains with gasoline, the flames self-extinguished before the body caught on fire.
Carol blamed Collier’s erratic and violent behavior on heavy drug use and said that after he dropped her off at home, he planned to lie low for a while, but she had no idea where he was hiding out.
Authorities placed Carol in protective custody at a local women’s shelter and conducted their search for Collier. He was later apprehended at the Giles home and taken in for questioning.
Speaking with investigators, Collier said Carol was the one who was using drugs and that it was her who had become suspicious of Billiter and attacked her that night. Collier claimed he watched as Carol used her late husband’s insulin syringes to inject Billiter with battery acid.
When the acid started to destroy the syringes, Carol switched to bleach, torturing Billiter to get her to talk. Collier said that Carol then suffocated Billiter with a rag doused in bleach.
Although Collier admitted to being an accessory to the crime, he claimed he did not carry out Billiter’s murder. He was then taken into custody, and authorities continued to keep tabs on Carol at the women’s shelter.
Investigators also obtained a search warrant for the Giles home, where they found evidence supporting both Carol and Collier’s statements to police. Inside Carol’s car, authorities discovered an empty plastic gas gallon as well as a container of battery acid. They also found a scrap of paper on the floor containing directions from West Bloomfield Township to Flint.
A search of the house uncovered blood spatter on the basement wall and multiple syringes, and up in the garage rafters, there was a mattress soaked in blood.
Investigators brought Carol back in for additional questioning, and once they confronted her with Collier’s claims, her story began to crumble.
Carol confessed that Billiter was killed not because she and Collier had suspected her of stealing, but because they were worried she had overheard a conversation in which Carol admitted to killing her husband, Jesse.
Following Jesse’s stroke, Carol began having an affair with Collier and, growing tired of caring for her ailing, diabetic husband, she filled Jesse’s syringe with an overdose of heroin instead of insulin. Carol claimed that Collier supplied her with the drugs to carry out the killing.
Due to Jesse’s various health issues, his murder initially went undetected, and an exhumation was ordered for his remains. After testing his organs, toxicology results came back positive for high levels of metabolized heroin.
Carol and Collier were charged with two counts of first-degree murder for the deaths of Jesse and Billiter. The couple was convicted in both cases, and they received two mandatory sentences of life in prison without the possibility of parole.
To learn more about the case, watch “Killer Couples” on Oxygen.com.
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