Police say exhaust remained so concentrated that firefighters needed breathing equipment before investigators could inspect the vehicle.
KEIZER, Ore. — A sealed residential garage, a running vehicle, an improvised exhaust tube and a gun now form the physical center of an attempted murder case involving an Oregon mother and her three young children.
Investigators say the garage at a home on Holly Court Northeast remained filled with dangerous fumes when police arrived shortly after 8:20 p.m. June 6. Officers could not safely enter until firefighters wearing self-contained breathing equipment opened and ventilated the space. Inside was the vehicle where Chardonnay Marie Benavidez, 32, allegedly tried to kill herself and her three sons with carbon monoxide. The children had already been moved to the living room and survived. The condition of the garage left authorities with a hazardous scene and a set of objects that may determine how prosecutors prove intent.
The first officers did not begin by examining the car. They began by confronting air that caused burning eyes and difficulty breathing near the garage, according to police. Those reactions forced them to withdraw and wait for crews trained to work in a contaminated space. Firefighters entered with protective equipment, opened the structure and allowed the exhaust to escape. Only then could officers document what was inside. Police said no responder required medical treatment. Authorities have not released instrument readings showing the concentration of carbon monoxide in the garage, the home or the passenger compartment. Such measurements, if taken, could help experts estimate the seriousness of the exposure, although changes caused by ventilation and the passage of time could limit any reconstruction.
Investigators found a makeshift device attached to the exhaust pipe and routed toward the vehicle’s interior. Public descriptions call it a tube or apparatus but do not identify its length, material or exact placement. Police have not said whether it passed through a window, door, trunk or opening in the body of the car. They also have not said how it was sealed or whether tools, tape or fasteners were recovered nearby. Those details matter because the state may use the construction to show preparation and purpose. The defense may examine whether the device worked as police believe, whether any part was moved during the rescue and whether investigators preserved the scene before the garage was opened and ventilated.
The vehicle itself may contain records beyond the visible tube. Investigators can examine fuel use, engine condition, electronic systems and surfaces for fingerprints or other traces. Public reports do not identify the car’s make, model or year. They also do not say whether police seized it, whether it remained at the house or whether specialists later tested the exhaust arrangement. The time the engine operated is based in part on an account that the family spent about 20 minutes inside. Authorities have not disclosed an independent record confirming that estimate. A modern vehicle may store limited operating data, but it is unknown whether this car retained information useful to the investigation.
The gun recovered from the passenger area or another part of the vehicle represents a second major category of evidence. Prosecutors said Benavidez told investigators that she planned to shoot herself if the gas killed her sons but left her alive. Police have not provided the weapon’s make, ownership history, ammunition status or location within the car. No report says it was discharged. For the state, the gun may support the claim that the alleged event was a planned murder-suicide rather than an accidental exposure. For the defense, the circumstances of its discovery and the precise wording of any statement about it may require close review. Investigators will need to connect the weapon to the alleged plan through admissible evidence, not merely its presence in a family vehicle.
By the time authorities secured the garage, Benavidez had already called 911. She reported that the children were falling in and out of consciousness after she attempted to kill them and herself with carbon monoxide, police said. Officers found her and the boys in the living room rather than in the vehicle. The children were twin 2-year-olds and a 4-year-old, all boys. Prosecutors allege that Benavidez had told them they were having a sleepover in the car. Authorities said she removed them when they showed signs of distress. The emergency call and relocation of the children create a documented break between the alleged exposure and the police discovery of the physical scene.
Medical evidence may help connect those two parts of the timeline. Benavidez and the children went to Salem Hospital for treatment related to carbon monoxide exposure. The boys were medically cleared June 7 and released to their father with help from the Oregon Department of Human Services. Officials have not made their test results public. Benavidez remained under a physician’s hold, received a psychiatric evaluation and was cleared before police arrested her. Blood testing conducted soon after exposure can assist doctors and investigators, but the significance of any result depends on timing, treatment and other factors. No public report has stated the measured exposure level for any family member.
Digital evidence could provide a separate path to the same alleged intent. A prosecutor said Benavidez researched possible methods for about a week and considered more than one option before selecting carbon monoxide. Officials have not identified the search terms, websites or devices involved. They also have not said whether the research was recovered through consent, a warrant or statements made during questioning. Dates and timestamps could either support or challenge the prosecution’s timeline. The defense may seek full search histories rather than selected entries, along with information showing who had access to each device. No released court record has established the scope of the digital investigation.
Statements attributed to Benavidez will likely require similar scrutiny. Police say she made admissions during the 911 call and later described her research, purpose and backup plan involving the gun. Courts may need to determine when each statement was made, whether she was in custody, whether officers advised her of her rights and whether her physical condition affected the reliability of what she said. Carbon monoxide exposure and an acute mental health crisis could become relevant factual issues without automatically making a statement unusable. The prosecution and defense will rely on dispatch recordings, officer video, medical timelines and witness testimony to place the statements in context.
The state charged Benavidez with three counts of first-degree attempted murder and three counts of first-degree assault, according to published accounts. Prosecutors allege that the boys were targeted through one scheme, but each child is treated as an individual victim. To prove attempted murder, the state must establish the required intent and conduct that moved beyond preparation. The tube, operating vehicle, time inside, children’s symptoms and Benavidez’s reported words make up the early prosecution theory. The defense has not publicly presented its own reconstruction. Until the evidence is admitted and tested, the state’s description remains an accusation.
The investigation also contains basic unanswered questions. Authorities have not explained what prompted the alleged plan, whether anyone communicated with Benavidez earlier that day or how long the apparatus had been in place. They have not identified the last person outside the immediate family to see the children before the incident. It is unknown whether neighbors heard the vehicle, whether a security camera recorded activity around the garage or whether exhaust entered other parts of the home. Police said they knew of no prior cases showing Benavidez was dangerous to the boys. The children’s father said her alleged conduct was sharply different from the mother he knew.
A Marion County judge ordered Benavidez held without bail during the initial proceedings. Early coverage listed a June 17 return to court, but no verified public update reviewed here established what occurred at that hearing. The prosecution may still obtain expert analysis of the car, garage air, medical records and digital devices. Defense lawyers may request independent testing and challenge how evidence was collected. A future filing could also clarify whether the case remains on its original charges, whether a grand jury acted and whether a trial or plea hearing has been scheduled.
The garage has been ventilated and the children have left the hospital, but the objects recovered there remain central to the unresolved case. The next documented court action should show which evidence prosecutors intend to rely on and which parts of their reconstruction the defense will contest.
Author note: Last updated July 11, 2026.