According to case records, it was around the time she started working for the MCSO that Macumber started suspecting his wife of cheating on him.
Carol's co-worker and close friend Frieda Kennedy later told Macumber's attorneys that the Sheriff's Office at the time was a "playhouse" environment, where "deputies would hit on the girls [who] worked in the office, telling us we looked pretty and asking us to go out for coffee." Coffee was innuendo for having "a relationship," she explained.
Kennedy told Macumber's lawyers that she thought Carol was seeing three deputies. Macumber, Kennedy said Carol told her, was a fine father but a bit of a "country bumpkin."
One spring night in 1974, Macumber recalled in trial testimony, he asked Carol to return home early to relieve the babysitter so he could attend a meeting concerning one of their sons' activities. Carol came home at 3 a.m., Macumber said in court. He testified that he asked her where she'd been, and she said it was none of his business.
Macumber said he brought up divorce, making it clear that he wanted to keep the children and the property; she could take the car and her belongings.
Carol protested, Macumber said in court, saying she wanted half of their estate and that she would get a lawyer to fight for it.
The court record goes on to detail that Macumber said they went to the bedroom, and after they lay in bed for about 20 minutes, Carol turned to him and asked, "Do you remember the kids in Scottsdale?"
He recalled responding, "What kids in Scottsdale?"
They separated in April 1974. Bill stayed in the house with the boys, and Carol moved into an apartment with Kennedy, her co-worker.
Then, in August, a gunshot came from behind Macumber's house — the bullet traveled through a window and narrowly missed his head.
Carol became a suspect in the shooting, MCSO reports show.
Around that time, records show, Carol also was involved in an internal investigation at work over her alleged office relationships.
At one point in the apartment they shared, Kennedy said, Carol claimed that her husband had mentioned something shocking a few months earlier. Kennedy continued that Carol said Macumber had confessed to killing two young people in Scottsdale in 1962.
On the morning of August 28, 1974, Macumber drove to the Sheriff's Office for what he was told would be an interview about the suspicious shooting at his house.
According to court testimony about the interrogation, when investigators asked if he thought Carol was capable of committing the crime, he said yes. But Carol already had made a statement of her own. Without a tape recorder or someone to take detailed notes on hand, Macumber was interrogated about Carol's statement — in which she'd implicated him in the double murder.
In court testimony, investigators recounted the interrogation, saying Macumber was cooperative but agitated — and surprised. One detective said Macumber was asked, "Bill, you did tell Carol that you shot those kids, didn't you?"
Carol claimed in her statement that Macumber said the Army had commissioned him to assassinate two people but that he'd shot the wrong couple. She told investigators that Macumber admitted to following the couple down the dirt road, where he shot them from his truck's window, after which he rifled through the woman's purse to make it look like a robbery.
Carol related to MCSO investigators that she recalled a night in 1962 when Macumber returned home with blood on his shirt, telling her that three young men had jumped him with a tire iron. According to her, Macumber said he'd fought off the attackers, whom he'd stopped to help because their car was disabled. This must have been the night the couple was shot, she told investigators.
Macumber declined a polygraph test but agreed to have his house searched, his gun collected, and fingerprints taken. Investigators said the partial print — which had been disregarded years before because it'd been impossible to determine whether it was a palm- or fingerprint — matched perfectly with Macumber's palm.
After his parents posted bail, Macumber, then 39, moved in with them.
At trial, Macumber's defense attorneys questioned Carol's motives. What if she'd switched the print in the file? What if, his attorney argued, MCSO deputies had helped her so they could keep the office dating scandal quiet?
Investigators also said Macumber's pistol — the Ithaca .45 he'd surrendered 12 years before and had turned over to investigators after Carol's statement — now matched markings on three bullets plucked from the crime scene.
Carol may have tampered with these, too, his attorneys proffered. Investigators couldn't match bullet markings to the breach face, extractor, or firing pin of Macumber's gun, but they matched ejector marks to three of four bullets. The ejector leaves small indentations on the back of a casing and isn't typically used alone to determine a weapon's match. But the state called an expert witness who said the markings originated from Macumber's gun "to the exclusion of all others in the world."