Authorities discovered 3-year-old Roland Meza Sandoval dead at the house in the 1500 block of Quincy Canyon Road after responding to a report of a shooting there shortly after noon Jan. 16, according to sheriff's officials.
Tribal police arrived to find 32-year-old Julio Ricardo Monggiotti, the live-in boyfriend of Roland's mother, in front of the residence, holding an ax by his side and swinging it back and forth, according to the county Medical Examiner's Office.
The officers told the man to drop the tool, and he complied.
They then asked where they could find Roland's mother, Elaina Rose Welch, also 32. Monggiotti replied that Welch was in the home. When the officers told him they needed to speak with her, he turned and went inside.
Moments later, a gunshot sounded from within the house, and the officers called for backup support, sheriff's homicide Lt. John Maryon said.
While the personnel waited for deputies to arrive, Welch came outdoors carrying a shotgun at her side, walked through her front yard and down the dirt road in front of it, according to the autopsy document.
The officers approached her and told her to drop the weapon. She did so, then told them that her boyfriend had killed her son and put him in a freezer in a laundry room adjacent to her garage.
Deputies soon showed up, arrested Welch and began trying in vain to contact anyone in the home. About 2 p.m., a SWAT team went inside and found Monggiotti dead of a gunshot wound to the torso.
Authorities then searched the home, eventually finding the child in the freezer, wrapped in a sheet and covered by frozen food items. The dead child was unclothed and "frozen solid," the report states.
Welch was jailed on suspicion of killing her son and Monggiotti, but was released six days later pending further investigation.
As of this afternoon, the case "remains an open investigation and under review" with no charges filed, said Steve Walker, a spokesman for the District Attorney's Office.
According to the autopsy report, homicide detectives determined that a series of abusive episodes led to Roland's death. The mistreatment began Jan. 5, when Monggiotti became angry with the boy and punched and kicked him, and directed Welch to do likewise.
The boyfriend proceeded to order the mother to retrieve some masking tape, which they used to cover the child's eyes and mouth and to bind his arms to his side, according to detectives.
They then covered Roland with blankets and put him in bed in his room, leaving him there for a while before freeing him.
The next day, Monggiotti beat the toddler again and repeated the prior tape-and-blanket binding with help from Welch, according to the report.
A few hours later, Monggiotti decided to go to a store, so he and the mother took the boy out of his room, wrapped him in a sheet and moved him into the master-bedroom closet, the investigative document states.
When the couple returned, they discovered that Roland had stopped breathing. Unable to revive him with CPR and the Heimlich maneuver, they allegedly washed the boy's body with bleach, wrapped him in a sheet again, put him in the laundry-room freezer and secured the lid of the appliance shut with a plastic tie.
Postmortem exams determined that the boy succumbed to suffocation. Listed in the autopsy report as contributing causes to his death were "multiple blunt-force injuries."