Detectives say evidence supports a second-degree manslaughter charge against the boy's mother, according to records obtained by The Herald this week.
A witness reported that the woman said she'd given the boy aspirin for a fever the evening before he died.
Toxicology tests showed that the boy, who was developmentally delayed, ingested a lethal amount of salicylates, a chemical common in aspirin and numerous other over-the-counter drugs.
A Monroe detective, however, acknowledged in his Aug. 20 memo to prosecutors that "critical evidence, which may have supported or ruled out more serious charges by autopsy, is not available for this case."
The Snohomish County Medical Examiner's Office declined to conduct an autopsy, making it difficult to determine how the drug ended up in the boy's system and what specific medication was ingested.
Yet, investigators point to more than two dozen pieces of evidence to support criminal charges against the boy's parents.
The "totality of the circumstances surrounding the life and death of (the boy) have led" to the recommended charges, Monroe detective Spencer Robinson wrote in the memo outlining the case.
Along with believing that negligence involving the woman caused her son's death, investigators say there is evidence to support charges of reckless endangerment, criminal mistreatment and tampering with physical evidence against both adults.
No charges have been filed and no arrests have been made.
The case has been assigned to a deputy prosecutor in the special assault unit, which handles child abuse cases. Robinson last week delivered seven volumes of case reports to the county lawyers, including his previous criminal investigation into the family and other referrals made to Child Protective Services.
The boy and his older brother were removed from their home for three months in 2010 after they were found living in squalor. Their father later pleaded guilty to reckless endangerment.
Prosecutors expect it will take some time to thoroughly review the death investigation and reach a decision on whether to file charges. Police also could be asked to do some follow-up work, depending on the prosecutor's review.
In his memo, Robinson outlines instances when the parents reportedly gave conflicting accounts of what happened prior to their son being taken to a Monroe emergency room.
The woman allegedly told police her son, identified in court papers as "A.J.," was not experiencing any physical symptoms of being ill and they hadn't given him any medication the night of his death.
Investigators say they have evidence that the woman posted messages to her Facebook page that night about her son having a fever.
"Tired! I have a feeling it is going to be a long night with (A.J.) feeling sick," the woman allegedly wrote around 12:30 a.m.
The father reportedly told police that he woke up around 3:20 a.m. and felt like he needed to check on his son. The parents reported that the boy was breathing and alive when they left their home, about two miles from the hospital.
That conflicts with observations from doctors, who reported that the boy was cold to the touch and in early stages of rigor mortis when he reached the emergency room. That led doctors to believe A.J. had been dead for a significant amount of time.
The father reportedly asked emergency room staff if the medical examiner would be conducting an investigation.
The medical examiner, however, classified the boy's death as "low suspicion," and declined repeated requests by police to do an autopsy. The boy's body was released to a funeral home just hours after the medical examiner took custody.
By the time police were told about the blood test results, the body had been cremated.
A social worker and the family's primary care doctor both told police they encouraged the parents to request an autopsy. They advised the family that an autopsy could be helpful to determine what caused the boy's seizures, which could be helpful to their care of their older son.
The parents reportedly told police that their doctor didn't recommend an autopsy.
Investigators say they also became suspicious after visiting the couple's home four days after A.J.'s death. They said the boy's room appeared "staged."
When they returned with a search warrant after learning the results of the toxicology tests, a blanket they had observed earlier on the boy's bed was missing. Detectives had seen stains on the blanket in their previous visit.
Additionally, they said they didn't find any medications in the home that they'd expect to find in a household with children.
A witness visited the family a couple of days after A.J. died and told police "the house was so disgusting."
Witnesses reported talking to the couple about the boy's death. They said they were given conflicting accounts of what happened.
A.J.'s parents stopped cooperating with the investigation soon after his death.
Diana Hefley: 425-339-3463; firstname.lastname@example.org.
More Local News Headlines
Victims of Oso mudslide still await buyouts, 16 months later Study at Kayak Point Park will determine if clamming can return 7:38 a.m. Arlington’s former Food Pavilion gets remodel, two new stores Sultan seeks to save deteriorating mural that memorializes firefighters Fire District 3, Fire District 7 will meet to consider a merger Nature is at the root of new preschool in Monroe Front Porch: Help stuff a bus School winners
Our new comment system is not supported in IE 7. Please upgrade your browser here.