Steven Kurtz with the Dallas County medical examiner's office said Sherin Mathews was a victim of homicide but that he couldn't provide any other details from the autopsy at this point. The Texas attorney general's office must decide whether the full report can be released to the public, he said.
Police in Richardson have released their findings in Sherin's October death to the Dallas County district attorney's office, and a grand jury this month is expected to review charges filed against the girl's adoptive parents, Wesley and Sini Mathews.
The couple is being held at the Dallas County jail: Wesley Mathews is held on a $1 million bond and faces a charge of felony injury to a child, while his wife has a bond of $250,000 on a charge of abandoning a child.
Mitch Nolte, the attorney for Sini Mathews, told WFAA-TV that he's received a copy of the full autopsy report and that nothing in it implicates his client in the girl's death.
An attorney for Wesley Mathews, Rafael De La Garza, did not immediately return a call Wednesday for comment on the autopsy findings.
Wesley Mathews initially told police Sherin disappeared after he punished her by sending her out in the night to stand by a tree near the home.
He later told investigators Sherin had developmental disabilities and was malnourished. He described a special diet regimen in which she had to eat whenever she was awake in order to gain weight.
Mathews said he had been trying to get the girl to drink milk in the garage of their home, according to an arrest affidavit filed by Richardson police.
"Eventually the 3-year-old girl began to drink the milk. Wesley Mathews then physically assisted the 3-year-old girl in drinking the milk," according to the affidavit.
Mathews told police that Sherin choked and coughed and eventually he felt no pulse and believed the child had died. Investigators wrote that he "then admitted to removing the body from the home."
Sherin's disappearance in October generated a broad search involving a number of law enforcement agencies. Her body was found in the culvert Oct. 22.
Richardson police Sgt. Kevin Perlich would not say if additional charges could be forthcoming in light of the autopsy results, explaining that decision would be left to the district attorney's office. A spokeswoman for the office declined to comment.
The couple adopted Sherin in June 2016. Their 4-year-old biological daughter is staying with family in the Houston area.
This story has been corrected to show Sherin's body was found Oct. 22 not 24.
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