MARIETTA, Georgia (CNN) -

Whether the prosecution will seek the death penalty in Justin Ross Harris hot-car death case will be decided in two to three weeks, Cobb County District Attorney Vic Reynolds said Thursday.

Reynolds' statement came hours after the Georgia father was indicted by a grand jury on eight counts, including malice murder and two counts of felony murder.

"We're pleased with the pace and thoroughness of this investigation, which continues on today," Reynolds said. "The evidence in this case has led us to this point today. Whether it leads us to anyone else remains to be answered."

The next step will be to put Harris' case on Superior Court Judge Mary Staley's arraignment calendar, which should happen within three weeks, the prosecutor said. Motions will then be filed before the case goes to a trial calendar.

Reynolds declined to take questions or comment further, saying, "This case will be tried in a court of law," and not in the media.

If Reynolds seeks the death penalty, it will be for the malice murder charge, which alleges that Harris, who has claimed his son's death was an accident, premeditated the child's killing.

Harris' attorney, H. Maddox Kilgore, called the charges excessive, describing them as a part of the "state's maze of theories."

"It was always an accident. When the time comes, and we've worked through the state's maze of theories at trial, it's still going to be a terrible, gut-wrenching accident. And all the eccentricities and moral failings of Ross' life isn't going to change that," he told reporters.

The other five charges Harris faces 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 felonies of first- and second-degree 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.

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.

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 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.