Tahlequah — Temperatures inside the car where an 18-month-old child died last month may have reached 126 degrees or more within an hour, according to the investigating officer.

The child died Nov. 19 after being put in a car seat with the vehicle’s engine running and its heater on at Norris Park. Tahlequah Detective Jeff Haney said the child’s father, Cody Butler, 19, was arrested later that night for child neglect and potential charges of manslaughter.

Medical personnel said the child’s core body temperature read 108 degrees on a thermometer, though Haney said that is the maximum reading possible on the thermometer used.

Butler reportedly told Haney he had been visiting with a girlfriend at Norris Park. He later put the child into its restraint in the back seat of the car, and started the vehicle to warm it up as temperatures outside dropped and the child became tired. Butler then stood outside the vehicle, talking to his girlfriend, and checked periodically on the baby.

Butler told Haney he later noticed the child’s cheeks were purple. Haney said the child might have been in the car an hour when Butler made the discovery, took her from the car seat, and removed her coat. Butler’s girlfriend, who is reportedly a nurse’s aide, then began performing CPR on the child until an ambulance arrived, but she never regained consciousness.

Officials from the state medical examiner’s office believe the injuries to the child were consistent with hyperthermia from exposure to heat in the vehicle, and there were no physical signs of injury or trauma. Haney also said he found no sign of any alcohol, drug, or tobacco use by Butler during the probe. Tahlequah police officials have previously said the case appears to be a tragic accident.

Haney asked for and was granted permission to test the temperature inside the vehicle. He placed a thermometer inside and started the engine with the heat settings left the way they were found Nov. 19 – the fan on high, and the temperature control set just to the right of the halfway point between coldest and hottest.

After 20 minutes, the temperature inside the car reached 90 degrees; at 28 minutes, the thermometer read 101; at 45 minutes, the temperature was 117; and at one hour, the car’s temperature registered 126 degrees.

Haney conducted a second test by turning the knob to the warmest setting available, with the fan still on high. Within 30 minutes, the car’s temperature in the back seat rose to 117 degrees, and after an hour, reached 139 degrees. A digital timer malfunctioned during the second test by detectives, likely a result of the high temperatures, Haney said.

“It was extreme heat both times after 18 to 20 minutes in both tests,” said Haney.

Detectives opened the car’s door periodically to photograph the thermometer and timer during both tests, and Haney said temperatures inside the car never dropped while the door was open. Other tests showed the oxygen levels in the car were “perfect” after 40 minutes with the engine running, and there were no signs of other toxins in the vehicle.

Butler had reportedly owned the car only a few months.

Assistant District Attorney Doug Dry said he and other prosecutors have looked at Haney’s report and have discussed the case.

“I don’t anticipate filing anything until I first get that report [from the medical examiner],” said Dry. “We’re still reviewing the case, and we want to make sure we make the right decision. It’s such an important decision, so we want to collect all the information we can.”

Butler was booked into the Cherokee County Detention Center Nov. 19 and later released on bond, according to Haney.

The Daily Press on Wednesday was allowed to use the same thermometer detectives employed in their investigation. A similar test was conducted on a Ford Explorer, which likely is roomier inside than the car Haney tested. The fan in the mid-sized SUV was turned on high, and the temperature setting was moved just to the right of the halfway point. The thermometer was placed in the back seat.

After 25 minutes, the temperature inside the SUV had risen to 96 degrees; at 40 minutes into the test, the temperature was 100 degrees; and after an hour, temperatures had reached 104.