Surveillance footage supported the mother’s account that her children appeared uninjured before she left them with her boyfriend, records state.
PORTLAND, Ore. — A mother’s account of leaving her two young children with her boyfriend while she went to work has become a central part of an Oregon murder case involving the death of her 2-year-old daughter.
The boyfriend, Dison Ruda, 28, is accused of inflicting the head trauma that killed the girl after he took responsibility for the children on March 28, 2025. He has pleaded not guilty to second-degree murder, first-degree assault, third-degree assault and two counts of first-degree criminal mistreatment. Investigators say surveillance footage supported the mother’s timeline, while hospital findings and a medical examiner’s review contradicted Ruda’s claims that the child choked on rice or suffered her fatal injury by falling from a playground slide.
The family was living at the Bybee Lakes Hope Center, according to a probable cause affidavit described in local and national reports. The girl’s mother had recently started work at an engineering and logistics company. She told police that Ruda drove her to work on the morning of March 28 and then cared for the children. She said neither child had injuries when she last saw them. Outside surveillance video reviewed during the investigation corroborated the mother’s description of the family leaving the center, KATU reported.
The records do not publicly detail every place Ruda and the children went after the mother was dropped off. By late morning, however, they were at Blue Lake Park in Fairview. At 11:47 a.m., the Multnomah County Sheriff’s Office received a report of a man carrying an unresponsive child. A park nature superintendent saw Ruda with the 2-year-old in his arms. The toddler was unconscious and not breathing. Ruda appeared to be blowing air into her mouth while walking, the affidavit said.
The superintendent tried to get Ruda to put the girl down so CPR could be performed. He moved toward a blue Honda Odyssey before placing her on the grass. The employee then stepped in to provide aid. Ruda told her the girl had choked on rice. Acting on that information, the superintendent checked the child’s mouth and performed the Heimlich maneuver but did not find an obstruction. She also saw a younger child strapped into a car seat in the vehicle, according to the documents.
When deputies and paramedics arrived, they saw signs that the emergency might involve more than choking. The toddler had pronounced bruises on her chest, neck and jaw. Some marks appeared inflamed and became more visible over time. Responders did not believe the bruising was caused by efforts to save her or was consistent with food blocking her airway. A deputy described Ruda as calm and unconcerned, but the physical evidence, rather than any single interpretation of his behavior, became the basis for the broader investigation.
The girl was transported to Randall Children’s Hospital, where imaging revealed a severe injury to her brain. Doctors found a left-sided subdural hematoma, widespread swelling and a shift of structures inside the skull. The initial hospital assessment referred to bruising across the child’s body and possible nonaccidental trauma or strangulation. Blood was not flowing to the brain, and medical personnel reported that the brain and other organs had been deprived of oxygen. The child was pronounced dead less than 12 hours later.
The mother saw her daughter at the hospital and confronted the extent of the injuries for the first time described in the public record. “I think he hurt my daughter,” she told police, according to the affidavit. Her statement directed suspicion toward Ruda, but detectives still had to determine what happened through medical evidence, witness interviews and scene analysis. The sheriff’s office did not publicly identify the girl, saying the family should have an opportunity to mourn privately before her name formally entered court proceedings.
Ruda spoke with investigators through a Chuukese interpreter. In addition to the choking claim given at the park, he described an alleged fall from playground equipment. He said the toddler climbed the steps of a slide on all fours, fell from about 6 feet and landed on her forehead in the wood chips below. He said she did not regain consciousness. The account gave detectives a possible accidental explanation to examine, even though it differed from the reason he reportedly gave the superintendent during the rescue attempt.
Detectives documented the playground and tested the surface beneath the slide. One investigator recorded himself bouncing on the shock-absorbing wood chips. The medical examiner considered whether a short fall onto that material could account for a catastrophic subdural hematoma and bruising on many parts of the child’s body. The examiner also looked for the scrapes or abrasions that would be expected if the girl had struck the wood chips with her forehead. Those expected injuries were not present, according to the affidavit.
The medical examiner concluded that the child’s brain injury was caused by abuse. The official cause of death was an acute left subdural hematoma due to blunt-force trauma to the head. Other injuries were documented on the girl’s chin, chest, abdomen, neck, jaw and limbs. The examiner considered the cushioning surface, research on children’s short falls and the presence of injuries on body areas not commonly hurt in innocent activity. The manner of death was formally classified as homicide on March 16, 2026.
That finding allowed investigators to move from a suspicious-death inquiry toward an arrest, but it did not decide who was legally responsible. Detectives worked with the Multnomah County District Attorney’s Office and obtained a court-authorized warrant. Deputies and the U.S. Marshals Pacific Northwest Violent Offender Task Force located Ruda near Southeast 92nd Avenue and Southeast Powell Boulevard in Portland at about 6 a.m. June 10. He was booked into the county detention center on five felony charges.
The two criminal mistreatment counts reflect a part of the case that goes beyond the fatal-injury allegation. Oregon prosecutors commonly use criminal mistreatment charges when a person legally responsible for a dependent individual is accused of withholding necessary care or exposing that person to danger. The precise factual basis for each count will be addressed through the charging documents and later court proceedings. Public reports identify two children as having been in Ruda’s care, but they do not state that the younger child suffered the injuries found on the 2-year-old.
The mother’s timeline may help prosecutors argue that Ruda had exclusive or primary access to the girl during the period in which she was injured. Surveillance footage, work records and witness testimony could be used to define that window. Even so, access alone would not prove murder. Prosecutors must establish that Ruda caused the fatal trauma and possessed the mental state required by Oregon law. The defense can challenge the timing of the injuries, the medical opinions and the claim that no accidental event could explain the girl’s condition.
Ruda’s statements are also likely to receive close attention. Prosecutors may argue that the choking and playground accounts were inconsistent and were contradicted by the absence of an airway obstruction and the examiner’s findings. Defense attorneys may dispute whether the statements were accurately understood, particularly because an interpreter was used, or may argue that the two accounts described different parts of the same emergency. No publicly reviewed trial testimony has resolved those questions.
Sheriff Nicole Morrisey O’Donnell said the arrest resulted from months of work by detectives and partner agencies, including prosecutors, federal marshals, forensic specialists and clinicians. The investigation’s length shows the difference between suspicion and a case considered ready for prosecution. Authorities waited for medical review, tested an accidental-fall explanation and sought judicial authorization before taking Ruda into custody.
The charges remain allegations. Ruda’s not-guilty pleas preserve his right to challenge the state’s evidence, question witnesses and require proof beyond a reasonable doubt. No verdict had been reported as of Wednesday. The unresolved issue for the court is what happened after the mother left for work and before a park employee saw her daughter unconscious in Ruda’s arms.
Author note: Last updated July 15, 2026.