James VanCallis will likely be punished to spend the rest of his life behind bars when he is sentenced on March 30, according to court officials.
April's body was found along a hiking trail in Armada, Michigan, on July 24, 2014, and medical examiners were able to determine she died from blunt force trauma and neck compression. Police claim April's bra had been ripped off and that she was found in a wooded area with her pants and underwear around her ankles.
Authorities claim VanCallis killed April by stomping and beating her to death with his motorcycle helmet and law enforcement officials tell PEOPLE they believe the killer took several precautions to evade capture.
Prosecutors allege that VanCallis wiped his helmet clean of the girl's DNA and that they were never able to locate the clothing that he was seen wearing in surveillance video the night of the murder.
April was walking her dog at the time of the attack, and detectives were able to pull data from a sports application on her phone, showing that her walking speed had increased moments before she was attacked.
It took the jury six hours to return a verdict, officials confirm.