Court documents described Todd Carlisle Fisher as calm when he called the Glendive Police Department early in the morning on Oct. 16.
Fisher told the dispatcher that he'd been on the "river bottom" for two days and just came home to find his father was killed.
"I went up and saw my dad and, um, he's been murdered and our safe's been broken into," he said, according to court documents.
The dispatcher asked Fisher to reiterate, and he calmly replied again, charges state.
"He's been shot in the head, yes."
Less than a week later, authorities arrested Fisher, 44, on suspicion of killing his father, Wilbur Fisher, with a .357-caliber gunshot through the eye.
The Dawson County Attorney's Office, with assistance from state Assistant Attorney General Ole Olson, charged Fisher with deliberate homicide and tampering with or fabricating physical evidence.
Fisher made his initial appearance on Tuesday in the Seventh Judicial District Court in Glendive. Bond was set at $1 million, and his arraignment is scheduled for Nov. 28.
Wilbur Fisher, 80, had been getting medical attention since late May, when he was hospitalized after a fall. An Adult Protective Services representative was working with Todd Fisher on guardianship and said the son expressed great stress, court documents say.
A month later, Wilbur Fisher was back in the hospital. During that stay, Todd Fisher charged $10,000 to his father's credit card without permission, charges state. The Adult Protective Services worker told investigators that Wilbur Fisher said he didn't want his son to get in trouble for it.
Another witness told investigators that Wilbur Fisher often called his son names, saying he was "stupid," "dumb," and "good for nothing," charges say. Other witnesses said that the father-son relationship was strained.
Wilbur Fisher had a $60,000 life insurance policy in effect and a will that directed his property and bank accounts to his son, Todd Fisher, court documents say.
Some of those documents were found in the safe. Despite Todd Fisher's claim that someone broke into it, Dawson County Sheriff's deputies didn't see any sign of forced entry, court documents state.
After Todd Fisher reported his father's death on Oct. 16, law enforcement visited the Fisher home west of Glendive. Deputy Coroner Tyler Sihla estimated that Wilbur Fisher, who was found on a bed, had been dead for at least a day.
Dawson County Sheriff Ross Canen and Assistant Glendive Police Chief Jake Feist had several interviews with Todd Fisher over the following days. Charges say he gave several narratives about what he did prior to calling the authorities.
Todd Fisher eventually said the he left home on Oct. 14 because "he and his father feared that CIA agents were out to get his father," charges say. He said that when he returned two days later, the door had been kicked open and he walked upstairs to find his father.
Deputies found a .357 revolver in the bushes outside the Fisher home. It contained one spent cartridge in the chamber and five unspent cartridges, according to court documents.
One witness in the investigation, a Dawson County deputy who was a friend of Wilbur Fisher, received a voice message from Wilbur Fisher on Aug. 18. In the message, Todd Fisher was upset and screaming, saying that "he couldn't take it any longer," charges say.
Wilbur Fisher understood this to mean that his son was tired of taking care of him, according to court documents. Then he offered reassurance.
"I don't know what he means," Wilbur Fisher said. "I can take care of myself."