MARIETTA, Georgia (CNN) -- The Georgia dad whose toddler son died after being left all day in a hot car was indicted by a grand jury Thursday on eight counts, including malice murder and two counts of felony murder.
The malice murder charge alleges that Justin Ross Harris, who has claimed his son's death was an accident, premeditated the child's killing.
The other five charges are: first-degree cruelty to children, second-degree cruelty to children, criminal attempt to commit a felony (sexual exploitation of a minor) and two counts of dissemination of harmful material to minors.
According to the indictment, the grand jury found that on June 18, Harris "did unlawfully, and with malice aforethought, cause the death of Cooper Harris ... by placing said Cooper Harris into a child car seat and leaving him alone in a hot motor vehicle."
The two felony murder charges allege that Harris killed his 22-month-old son while committing the first- and second-degree felonies of cruelty to children. One count states he killed Cooper "maliciously," while the other felony murder count says Harris killed him "with criminal negligence."
Harris faces a mandatory sentence of life in prison if convicted on any of the murder charges, while a guilty verdict for the malice murder count could make him eligible for the death penalty.
By leaving Cooper in the car, Harris caused the boy "cruel and excessive physical pain," the cruelty to children charges allege.
The criminal attempt to commit a felony and dissemination of harmful materials charges are not related directly to Cooper's death. They involve allegations that Harris requested a nude photo of a minor's genitalia and sent the same minor descriptions of "sexual excitement and sexual conduct," according to the indictment.
A Cobb County detective testified at an earlier probable cause hearing that while Cooper was in the car at his father's workplace, Harris was sexting with numerous women and sent one of them, who was underage, a photo of his erect penis.
Harris pleaded not guilty to murder and child cruelty charges in June. Cobb County Chief Magistrate Frank Cox signed off on the charges, stating Harris would've had to notice that "the stench in the car was overwhelming" when he got in it as he left work and "drove it for some instance" before stopping to check on the boy.
Charges filed in an indictment supersede the previous charges. Harris has been held without bond since Cooper's death this summer.
Authorities have painted Harris as a terrible father who, after admittedly looking up online how hot a car needed to be to kill a child, purposely strapped his son into his sweltering SUV to die.
His motivation? The prosecutor has characterized Harris as an unfaithful husband who wanted a childless life.
Yet his attorney, H. Maddox Kilgore, has argued his client tragically forgot his child in the car. Friends described Harris as a doting dad, not a malicious one, who loved to show off his blond, bright-eyed boy and talked about him incessantly.
It all started simply enough: Harris left home with Cooper in a rear-facing car seat in the back of his 2011 Hyundai Tucson, then headed to his job as a Web developer for Atlanta-based Home Depot after making a quick pit stop at a fast-food restaurant for breakfast.
But he didn't follow through on his routine of stopping to drop the boy off at daycare.
Instead, according to a criminal warrant, Harris drove to work and left Cooper strapped in his car seat. He went back to his SUV during lunch, put something in the car, then returned to work.
All the while, the vehicle got increasingly hotter, with records showing the temperature topped 92 that day -- which can make the heat inside a closed vehicle soar past 100 degrees quickly.
Sometime around 4:15 p.m., seven hours after he'd arrived at work, Harris got back into his Hyundai and left work. Witnesses told police that, soon thereafter, they heard "squealing tires (as) the vehicle came to a stop" in a shopping center.
Cobb County Police Detective Phil Stoddard testified at the probable cause hearing that Harris got out of the car yelling, "Oh my God, what have I done?"
He then stood with a blank look, going to the other side of his SUV to make a phone call after someone told him that his son needed CPR, a witness told police, according to Stoddard.
Witness Leonard Madden testified that, upon leaving a restaurant, he noticed Harris was distraught and crying.
"He was hollering," Madden testified, recounting the father saying, "Oh, my God! Oh, my God! My son is dead!"
Harris had to be physically restrained once it became clear Cooper wouldn't make it -- at which time it was 88 degrees -- according to police.
Leaving his son alone in the car wasn't the only thing Harris did that day, authorities say.
While at work, he messaged six women besides his wife and exchanged explicit texts with some of them -- including the lewd photo that he sent to an underage female -- Stoddard testified.
Yet even after these allegations surfaced, his wife Leanna Harris stood by her man.
She sat calmly through the probable cause hearing, and at Cooper's funeral flatly insisted she was "absolutely not" angry with her husband.
"Ross is and was and will be, if we have more children, a wonderful father," Leanna Harris said at the funeral in Tuscaloosa, Alabama, a gathering that her husband also addressed via phone from the Cobb County Jail. "Ross is a wonderful daddy and leader for our household. Cooper meant the world to him."
CNN's Eliott C. McLaughlin and Greg Botelho reported and wrote from Atlanta, with Devon M. Sayers reporting from Marietta. CNN's MaryLynn Ryan contributed to this report.