Hearn added that Sabrina told him that Robert had a rare medical issue that caused stomach issues and vomiting. They believed the poison could go undetected because of the medical issue and the symptoms.
Hearn told investigators he began to research arsenic and how much dosage would be needed to kill a man. Hearn said he used a fake name and prepaid card to purchase the arsenic from a company that did not require a background check.
The documents show that Hearn tested the poison on a neighborhood dog who he believed was noisy. Hearn said he stopped hearing the dog days after he administered the poison, and believed the dosage had worked.
Hearn told investigators that during this testing stage, Sabrina began to pressure Hearn so that they could go through with their plan.
The documents say that Sabrina made banana pudding, which was Robert's favorite dessert, with the intent to put the arsenic in it so that he could eat it at work.
Hearn added that Sabrina wanted to poison Robert away from their home so that she would be less likely to be investigated. Hearn told investigators that Sabrina told him the Tehachapi hospital is a "little disorganized" and she did not believe they would find arsenic in his blood.
After placing arsenic in the pudding, Hearn told investigators that he and Sabrina began to worry that detectives could trace their calls and determine that they worked together to poison Robert.
The document says Hearn later asked Sabrina what had happened with the pudding. He told investigators that Sabrina said she had told Robert to throw the pudding away because it did not taste good and she had made an error when she was making it.