The injuries that led to the death of Demarcus Stokes in 2011 were extensive. The Baton Rouge toddler suffered bleeding under his scalp and on the surface of his brain, the doctor who performed the autopsy testified Monday at the first-degree murder trial of Randy Demond Parker.

Parker, 27, of Baton Rouge, was the boyfriend of the child’s mother, Kimyia Stokes, who remains jailed on an obstruction of justice charge in the case.

Police have said Parker, a convicted felon, beat the boy three times in less than 24 hours in October 2011 because the 23-month-old would not sit still for a haircut and after the child urinated on himself during the night.

Dr. Bruce Wainer, the pathologist who conducted the boy’s autopsy, said he found “a considerable amount of bruising” on the child’s head, torso, arms and legs. Some of the injuries were consistent with being punched, he testified.

Wainer also said he discovered traces of an anti-depressant drug used by adults in the boy’s blood.

Parker faces an automatic sentence of life in prison if convicted by state District Judge Trudy White as charged. Parker previously waived his right to a jury trial. Prosecutors are not seeking the death penalty.

East Baton Rouge Parish Assistant District Attorney Ron Gathe told White in his opening statement that Parker is guilty of first-degree murder because he intentionally killed a defenseless child in an Erie Street shotgun home where Parker lived.

Parker’s attorney, Benn Hamilton, accused police of immediately assuming foul play in the little boy’s death.

“There’s been a rush to judgment from the actual outset,” he told the judge, adding that Parker had no intention of killing or seriously injuring the child.

Police have said Parker and Kimyia Stokes, 26, of Baton Rouge, were in absolutely no rush to seek help when Demarcus stopped breathing.

Stokes, according to an affidavit of probable cause, said Parker beat her son three times between Oct. 22 and Oct. 23, 2011. She witnessed two of the beatings and heard her son screaming during the third, the affidavit says.

Parker said the last time he whipped Demarcus he used a belt, causing the toddler to hit his head, the affidavit states. After that beating, Parker told the boy’s mother he thought her child was dead.

Stokes told police that Demarcus was breathing irregularly about 1 a.m. on Oct. 23 and stopped breathing three hours later. Stokes and Parker dressed the child and “waited around trying to figure out what to do and say” before Parker finally called 911 about 6 a.m., the affidavit states.

Wainer said the boy’s fatal injuries were not accidental.

“How could you conclude from the autopsy that this was a homicide?” asked Hamilton, who suggested Demarcus could have fallen off the toilet.

Wainer said the pattern and nature of the injuries convinced him this was no accidental death.

“That’s purely speculation, isn’t it?” Hamilton inquired further.

“No, it isn’t,” Wainer replied. “These injuries were not the result of some freak accident.”

The trial will resume Tuesday.

Parker served six months in Parish Prison in 2008 after he was convicted of attempted second-degree murder. He served another six months a year later after he was found guilty of simply assault.

Follow Joe Gyan Jr. on Twitter, @JoeGyanJr.