ATLANTA (CBS News) -- The father of a Georgia toddler who died in a hot SUV told authorities that he did an online search about children dying in vehicles because he was afraid it could happen.
Justin Ross Harris faces charges of murder and second-degree child cruelty in 22-month-old Cooper Harris' death.
Search warrants released Saturday by Cobb County Police Department say Harris told police that he researched what temperature can cause a child's death in a car.
The warrants say police were looking for a laptop, electronic devices and evidence of child neglect or abuse at the family's Marietta home. Harris' phone and car were included.
Harris has told police he was supposed to drive his son to daycare but drove to work on June 18, forgetting the boy was in the car.
A medical examiner in Georgia says hyperthermia was the cause of death for the child.
The investigation hinges on a key question: Was the boy the victim of a horrific accident after his father simply forgot to take him to day care, or did the man know the child was inside when he left him strapped in for seven hours?
A warrant supporting the murder charge against the father states that Harris stopped with his son for breakfast and also returned to put something inside his vehicle around lunchtime while the child was inside it.
Harris has told police he was supposed to drive his 22-month-old son to daycare but drove straight to work on June 18 without remembering the boy was strapped in his seat until the ride home. After spending the day at work, he pulled into a shopping center parking lot and hysterically asked for help for his son.
Harris put the toddler in a rear-facing car seat in the center of the back seat of his Hyundai Tucson after eating at a Chick-fil-A restaurant the morning of the boy's death, the new warrant says. He then drove about 10 miles to work and left the child strapped into the car seat when he went inside, the warrant says.
At lunchtime, Harris returned to the vehicle and opened the driver's side door to place an object inside and went back inside his workplace, the warrant says. It does not explain how the officer knows that.
Around 4:15 p.m., Harris left work and, soon after, pulled over at a shopping center and asked for help with his child, the warrant says. The child was left in the vehicle for about seven hours, the warrant says. The temperature that day was 88 degrees at 5:16 p.m., according to the first warrant in the case, filed the day after the child died.
Neighbors and acquaintances of Harris and his wife described them as loving parents.
Their landlord, Joe Saini, told The Atlanta Journal-Constitution that the couple were "very, very nice" people who were in love with their baby.
"Everything was going right for this couple," Saini said. "They wanted to buy a house so they could have some space for their child to run around the backyard."