Father who left his 22-month-old son locked in a hot car found guilty of murder.

After five long weeks, a jury has found Justin Ross Harris guilty of murdering his 22-month-old son, Cooper.

Harris, 35, was initially thought to have been suffering from Fatal Distraction Syndrome when he left the infant locked in a hot car for seven hours in 2014, however his actions were deemed deliberate at trial.

On that same day Harris’ phone records revealed he was ‘sexting’ five women and a minor while his toddler languished in the heat, CNN reported.

In court, prosecutors claimed the web developer killed his son to escape the responsibilities of family life.

“This is one of those occasions where actions speak louder than words,” Cobb County Assistant District Attorney Chuck Boring said after delivering the verdict.

“He has malice in his heart, absolutely.”

The jurors considered the testimony of seven witnesses and more than 1,150 pieces of evidence, including the SUV in which Cooper died in a suburban Atlanta parking lot.

On June 18, 2014, Harris strapped his son into the rear-facing car seat of the Hyundai Tucson and drove from their home in Marietta, Georgia, to a nearby fast food restaurant for breakfast.

Instead of dropping the child at day care, as was usual, he drove to work, leaving him in the locked car, in the car park for his entire shift.

Sometime in the afternoon he drove to the movies, which is when he discovered Cooper had died.

Witnesses said he appeared distraught and was screaming, but it was later revealed he had posted a message online just minutes before locking the car door.

“‘I love my son and all, but we both need escapes.’ Those words were uttered 10 minutes before this defendant, with a selfish abandon and malignant heart, did exactly that,” Boring said.

During the trial Harris’ ex-wife, Leanna Taylor, testified on his behalf, saying that while he has “destroyed [her] life”, he was a loving father who would not hurt his son on purpose.

“Cooper was the sweetest little boy. He had so much life in him. He was everything to me,” she told the court through tears.

Harris will be sentenced on December 5 and faces a maximum sentence of life without parole.