An Arkansas State Crime Lab medical examiner during the second of a three-day capital murder trial said that the 3-month-old victim did not die accidentally and that the baby sustained injuries possibly days before he died.

What was alarming, Associate Medical Examiner Adam Craig said, was that nothing referencing these types of injuries was ever reported to authorities during the initial investigation of baby Mitchell Atwood's death.

Mitchell Atwood died of blunt force trauma on May 31, 2016. The infant's stepfather, 31-year-old Zachary Lynn Atwood, was subsequently charged with manslaughter after admitting to sitting on the baby the day the infant died. Charges were later upgraded after an autopsy report revealed findings of foul play.

During an autopsy he conducted, Craig said he found multiple exterior and internal injuries on the 3-month-old. When questioned by deputy prosecutor Colin Wall, the associate medical examiner said "someone would have sought medical attention" for the types of injuries the 3-month-old endured.

The infant's death was ruled a homicide and not an accident due to the extent of the injuries and also because nothing hinting any past incidents to indicate such injuries was ever mentioned to investigators, Craig, who was declared an expert witness, testified.

Craig was one of three who testified Tuesday. Michelle "Sunnie" Thomas and Arkansas State Police Investigator Mike Garlington also testified Tuesday. Thomas was married to Zachary at the time he allegedly killed 3-month-old Mitchell. The two were legally divorced, she said, in October 2016.

The courtroom was filled with a variety of emotions Tuesday. As Thomas testified about her memory of the day her baby died, her family cried out in the audience as she wept on the stand, and when Zachary's interrogation videos were played before jurors, the family gasped in anger at times, and cried following other portions of the videos.

Thomas said Zachary was not Mitchell's biological father. In a video played before the court later on in the day, Zachary said he was aware the baby was not his but also that he "loved that baby as my own."

While married to Zachary, the late infant's mother said she did not work because "he wouldn't allow it." At one point, she admitted the two separated for some time because she was tired of being abused.

Thomas initially left Zachary after he was jailed. She recalled his anger issues and said when she had hurt her leg and had to use crutches, he would take her crutches and throw them to "make me crawl to get them."

She did not deny using methamphetamine. Thomas said she, Zachary and Vicky Archer, who is Zachary's mother, all lived in the home and used methamphetamine. The couple's 5-year-old daughter also lived in the apartment the three adults shared in Guy. Zachary would inject himself with meth before injecting her while Archer "would smoke" her share. Thomas said she, Zachary and Archer all used meth on the night before her baby died as well as the morning in question.

On the day in question, Thomas said Archer left with her 5-year-old daughter to walk to the Thunderbirds Citgo. This was a common occurrence, she said, because Archer worked at the gas station, it was within walking distance and none of the adults at the home owned a vehicle. Before the baby's grandmother left with his sister, Thomas said she and Zachary were in the back bedroom attempting to have sex but that Zachary "was unable to perform."

This angered Zachary, she said. In her testimony, she also said she remembered the baby crying as the two were in the back bedroom. Zachary got up, told Thomas not to worry and that he would tend to the baby. After her then-husband got up to check on the baby, she went to take a shower. Soon after she got out of the shower, she was in her bedroom when she heard a "God-awful scream."

The scream was her daughter's after the 5-year-old and Archer found Mitchell lying lifeless in his portable crib.

The baby was blue, and she said she remembered looking over at the baby before taking her shower but that she did not touch the baby because she thought the baby was sleeping and did not want to wake Mitchell. She began to talk quickly as she sobbed, recalling questioning Zachary about whether he washed his hands when he left to make the baby a bottle because she "didn't want meth to get to the baby" to learning her baby had stopped breathing to Zachary pushing her to the ground as she ran to call for help from her neighbor's phone.

"He just looked peacefully sleeping .. I wish I would have touched him to see if he was OK," she said of the last time she peeked at her 3-month-old baby.

Investigator Garlington said he never believed Zachary was telling him the truth when questioning him about the baby's death. While he knew little about the case, he knew the baby had suffered blunt force trauma to the head.

At first, Zachary denied knowing anything. Hours of his interrogation footage was shown before the jury, portions of the questioning was omitted after Circuit Judge Charles "Ed" Clawson Jr. ruled Monday that statements regarding past arrests and alleged animal abuse could not be admitted as evidence during the guilt phase of the Atwood Trial.

Zachary was seen fidgeting with his hands and showing "symptoms of methamphetamine use" during his June 2, 2016, interview with Garlington.

Garlington, former Guy Police Chief Bobby Lockard and the late Coroner Pat Moore were each present for Zachary's first interrogation.

At one point, Garlington asked if the infant's death could have resulted from an accident, possibly squeezing the baby too hard while walking around doing laundry.

Eventually, the ASP investigator told Zachary he knew he was lying because Mitchell's injuries showed "someone smashed his head [or] put something over his head."

Garlington said he found it odd and suspicious that Zachary "would cry but shed no tears" during the first round of interrogations.

"Every time you say you love him, you look away," Garlington said to Zachary on June 2.

Garlington also told Wall he found it odd that Zachary referred to Mitchell as "that baby" or "the boy."

The term "murder" was never brought up until Zachary said he felt he was being "framed for murder" by investigators and the 3-month-old's biological father.

Garlington walked away from Zachary briefly on June 2, leaving him in a room at the Faulkner County Sheriff's Office Criminal Investigation Division with Moore and Lockard. While the investigator was away, Zachary pleaded to Lockard that he was scared of Garlington.

"Bobby ... he's freaking me out," Zachary said. "My head is pounding, my blood pressure is skyrocketing. ... What do I need to say? I don't understand."

The next day, Zachary was interviewed by Garlington a second time.

Garlington said Zachary was "genuine" during the second interview and began to show signs of "real emotion."

During this interview, Zachary said he confessed to sitting on the baby by accident.

"I accidentally sat down and his f***ing head was like right there," Zachary said, adding that he was too scared to tell anyone about what happened because he didn't want to "go to prison for murder over an accident."

However, Craig testified the injuries baby Mitchell sustained could not have come from sitting on the baby while the baby was lying on a couch.

Baby Mitchell showed to suffer from several injuries including:

Multiple blunt force trauma areas. A skull fracture. Cerebral hemorrhage. Cerebral contusion. Contusions on his scalp, nose, an arm and a foot. An older subdural hematoma. Retinal hemorrhages.

Moments before Craig took to the stand late Tuesday, deputy prosecutor warned family members in the audience that the testimony would get graphic. All but two family members left the gallery as autopsy photos graphically detailing the baby's injuries were displayed before the court.

With each photo that pinpointed and documented the baby's many injuries, Craig explained how such injury could occur and the process of examining such injuries.

The way hemorrhages appeared in the baby's eyes and how the brain was bruised "suggest some sort of acceleration and deceleration," he said.

In his testimony, Craig also said the injuries the baby sustained likely would have occurred "at least one day" prior and that the baby was dead longer than the time frame Zachary, who was the last to see the baby alive, told authorities.

When a photo previously shown as evidence in the case showed what appeared to be bruising on the baby's neck and back, Craig said that would have been livor mortis, which is a discoloration on the skin after blood pools to the lowest part of the body.

Previous testimony said the baby was found lying facedown by Archer.

Testimony in the capital murder case is scheduled to resume at 9 a.m. Wednesday in Courtroom 3D of the Justice Building on South German Lane in Conway.