A Richardson man accused of killing his adopted daughter, Sherin Mathews, and dumping her body in a culvert pleaded guilty to a lesser charge Monday, the day his capital murder trial was set to begin.

Wesley Mathews, 39, pleaded guilty to injury to a child by omission. If he'd been found guilty of capital murder, Mathews would have faced an automatic life sentence without parole for the 3-year-old girl's death in 2017.

Mathews could still face life in prison and prosecutors urged the jury to choose that sentence. But the jury could decide on a lighter sentence during the punishment phase, which got underway Monday after the guilty plea.

Wesley Mathews, 39, is accused in the 2017 death of 3-year-old Sherin Mathews.

Police found Sherin's body in October 2017, two weeks after Mathews reported her missing. During those two weeks, prosecutors say Mathews led investigators, volunteers and the public on a "wild goose chase" to find his daughter, though he knew she was dead.

He initially told police Sherin disappeared on Oct. 7, 2017, after he left her outside the family's home as punishment for not drinking her milk. He called officers five hours after her disappearance, and when they arrived, led them to an area of trees near his home where he said he last saw the child.

"All the while, the defendant knew exactly where she was," lead prosecutor Jason Fine told jurors Monday.

Mathews later told police the child died because she choked while he "physically assisted her" with drinking her milk.

Fine said that Mathews' character and his actions following Sherin's disappearance will persuade the jury that it is "left with only one just verdict" -- life in prison.

Rafael De La Garza, Mathews' attorney, asked the jury for leniency in his client's punishment. He noted that Mathews doesn't have a prior criminal history and argued that he isn't a threat to the public.

He said Mathews is remorseful and is expected to testify to provide an honest description of what transpired the night Sherin died.

"He is just heartbroken about the poor decisions he made," De La Garza said. "About the lies he gave on that day."

Defendant Wesley Mathews (left) enters the 282nd Judicial District Court at the Frank Crowley Courthouse, on Monday, June 24, 2019. Mathews, who is accused of killing his 3-year-old adopted daughter Sherin Mathews and dumping her body in a culvert, pleaded guilty to injury to a child by omission. (Tom Fox / Staff photographer)

Prosecutors planned to show evidence that Mathews and his wife, Sini Mathews, failed to provide adequate care for Sherin after the couple adopted the toddler in 2016 from India.

Multiple speech and physical therapists testified that the couple regularly failed to bring Sherin, who had special needs, to appointments. She was scheduled to have weekly physical therapy sessions to improve her walking from January to May 2017, but she only appeared for eight sessions during that five-month span, one therapist testified.

Prosecutors also tried to suggest Wesley Mathews didn't initially care that his daughter was missing. Jeremy Savage, the Richardson police officer who responded to Mathews' 911 call, told the jury Mathews was noticeably calm when he arrived at the home.

Jurors watched excerpts from Savage's body-cam footage of the morning Sherin went missing. He asked Mathews why he'd waited five hours to report her disappearance. Savage later noticed Mathews had washed laundry just before the officers arrived, which he thought was odd.

"If you're searching for your child and have great concern for where your child is at, you're not doing laundry," Savage said.

Police charged Sini Mathews with child abandonment in November 2017, but the charge was dismissed in March after prosecutors determined they couldn't prove her guilt beyond a reasonable doubt. She has been called to testify at her husband's trial, according to a court document filed in April.

Wesley Mathews' trial resumes Tuesday, and attorneys for the state are expected to call on at least four additional witnesses before they rest their case.