A Texas grand jury has returned an indictment against the adoptive father of 3-year-old Sherin Mathews, charging him with the little girl’s murder.
PEOPLE obtained a statement from the Dallas County District Attorney’s Office that confirms Wesley Mathews, 37, could face the death penalty if convicted.
The indictment comes three months after Sherin vanished from Richardson, Texas, after her father allegedly said he left her outside as punishment for not drinking her milk.
Her body was found in a culvert drain weeks later.
Earlier this month, medical examiners concluded that Sherin died from “homicidal violence,” but could not specify exactly how she died, as her remains were already in an advanced state of decomposition.
Wesley Mathews is also charged with injury to a child, abandoning a child and tampering with evidence.
During a press conference, Dallas County District Attorney Faith Johnson told reporters her office is committed to seeing justice is served.
“We will be tenacious, we will be persistent and we will prosecute this case to the fullest,” Johnson said, noting she has yet to decide if she will seek the death penalty.
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Johnson said she will not be releasing any more information about the case before taking it to trial.
The girl’s adoptive mother, Sini Mathews, was also indicted by a grand jury on an abandoning a child charge.
Authorities allege Sini and Wesley Mathews left their adoptive daughter Sherin alone on the evening of Oct. 6, 2017, to take their 3-year-old biological daughter out to dinner.
The little girl was adopted from India in 2016.
Wesley Mathews was arrested on Oct. 7, 2017, after allegedly telling investigators he punished Sherin for not drinking her milk by leaving her to stand next to a tree outside their Richardson home.
He allegedly told police he placed her near the tree at around 3 a.m.
Mathews allegedly said he went to check on the toddler about 15 minutes later but she was gone. She was reported missing 5 hours later.
He later allegedly changed his story, telling police he watched his daughter choke on milk and die, according to an arrest affidavit previously obtained by PEOPLE. After her death, he says, he removed her from the home.
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The affidavit says that Matthews was “trying to get the 3 year old girl to drink her milk in the garage…. Wesley Mathews said she wouldn’t listen to him.” Mathews then allegedly stated that he “physically assisted” her in drinking her milk, “and the girl choked.”
Wesley Mathews had been previously charged with felony injury to a child soon after Sherin’s remains were found.
Sini Mathews was arrested weeks later, and charged with abandoning or endangering a child.
Both are still in custody and have yet to enter formal pleas to the charges against them.
PEOPLE has been unable to reach either of their attorneys for comment.