A Georgia man is facing murder charges after leaving his 22-month-old son strapped in a car seat in the family's SUV for seven hours on a day last week when temperatures climbed to the high 80s, according to an updated arrest warrant released Wednesday.
The results of an autopsy, also released Wednesday, showed that Cooper Harris died of hyperthermia, with the death described as a homicide.
The boy was the 13th child in the U.S. this year and the sixth this month to perish after being left in a car.
"I understand that tragic accidents similar to this one do occur and in most cases the parent simply made a mistake that cost them the life of their child," Cobb County Police Chief John Houser said in a statement. "The chain of events that occurred in this case does not point toward simple negligence and evidence will be presented to support this allegation."
Harris is being held without bond, facing charges of murder and second-degree cruelty to a child, a felony. A bond hearing is scheduled for July 3.
The updated warrant offers new details on the hours leading up to the death of the boy June 18.
Justin Ross Harris told police he had buckled his son into the car seat before heading to his job at a Home Depot corporate office in Atlanta. On the way, Harris said, he was supposed to drop off his son at daycare.
While driving home from work a little after 4 p.m., Harris told police, he suddenly realized his son was in the car and he pulled into a shopping center parking lot, where he and others tried unsuccessfully to revive the child.
The updated warrant, however, says that Harris and his son stopped for breakfast on the way to work and that witnesses told police that, while at work, the father returned to the SUV and opened a door, suggesting he knew his son was in the car.
Harris does have supporters. An online petition on change.org seeking to have the Cobb County district attorney drop the murder charges has more than 11,000 signatures.
"People don't understand how our memory can let us down," Janette Fennell, founder and president of KidsandCars.org, a nonprofit child safety organization, told the Los Angeles Times on Wednesday. "The biggest mistake people make is saying, 'This could never happen to me.' "
Since 1998, 619 children have died from heatstroke after being left in cars, according to a study by San Francisco State University -- an average of 38 fatalities a year.
About 70% of the children were 2 years old or younger, according to the study. It also found that more than 50% of the incidents were the result of a parent or caregiver accidentally leaving the child. In about a third of the cases, the children somehow got into the vehicles on their own and then couldn't get out.
In less than 20% of the cases, the child was intentionally left in the vehicle -- either because a parent planned to run into a store for a few minutes or because of issues with alcohol and drugs or child abuse.
According to warnings issued by the National Highway Traffic Safety Administration about leaving children in vehicles, cars act like greenhouses. In the 10 minutes after a car has been parked, its temperature can rise by 20 degrees. In an hour, it can be 40 to 50 degrees hotter. Children are particularly vulnerable because their internal temperatures rise five times faster than an adult's.
Since 1998, when it became illegal to let young children ride in the front seat of a vehicle because of airbag deaths, the number of children left in cars -- mostly in the back seat -- has soared, according to statistics gathered by KidsandCars.
Fennell said that in the great majority of the cases she has seen, the parents weren't trying to harm their children. Changes in routine, stress and lack of sleep often lead to the tragedy, she said.
Mary Parks of Virginia lost her 23-month-old son, Juan, in 2007. She thought she had dropped him off at daycare before heading to work, and she went to pick him up there at the end of her day.
"The teacher told me Juan wasn't there and I went running to my car," Parks told the Los Angeles Times.
She said she didn't think her son was anywhere but daycare all day, and even spoke to her sister-in-law while at work that day and remembers telling her that Juan was in daycare.
"What happened is that you're human and you failed," she said.