Prosecutors painted a picture of a man who came with a sinister plan and armed to kill. They showed jurors graphic photos from inside the house on Falling Oaks Road from Aug. 8, 2015. The images prompted some of the victims' family members to leave the courtroom.
SEE RELATED STORY: Mom of victim in 2015 massacre called for help multiple times before family was found dead
The photos showed eight people dead, six of whom were children. Some of the kids' bodies were shown to have been handcuffed to bunk beds, and the parents' bodies were also seen restrained in the master bedroom.
Dr. Myles McClelland worked alongside Harris County Sheriff's Office's SWAT team. He was with the team when they responded to the scene of the crime and entered the residence. McClelland testified before the jury on the horror he saw inside the house and said there was no hope on reviving any of the victims.
WATCH: JAILHOUSE INTERVIEW: Mass killing suspect speaks his mind
"The door was blocked by a body," McClelland said during his testimony. "I had to take off my vest and climb through."
As images appeared at the trial of the heartbreaking scene, Conley showed no reaction and held his head down.
Sgt. Cathy Helstrom with the sheriff's office also testified. She worked as a crime scene investigator on the case, and on Wednesday, she described the volume of evidence.
Helstrom said shell casings were found near children's books and toys in the bedroom. She said investigators also found a pistol that was still loaded on the kitchen table, and cell phones found inside a kitchen drawer, far from the bedrooms. Helstrom said deputies even recovered a black backpack in the master bedroom with rolls of duct tape, handcuff keys and gloves.
Judge Chuck Silverman, Conley's defense team and state prosecutors all agreed to shut out cameras from the courtroom. They denied the public easy access through video recordings in an attempt to follow the case that stunned the city six years ago.
If Conley is convicted, the death penalty is off the table in the capital murder trial for the deaths of Dwayne and Valerie Jackson. Conley's defense team said he is intellectually disabled, and the U.S. Supreme Court has ruled death cannot be a punishment.
Prosecutors expect to hand the case to the jury by the end of the week.
SEE ALSO: Man accused of killing 6 kids in family massacre won't face death in Harris County
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