File: Pieter Doorewaard and Phillip Schutte were found guilty of killing teenager Matlhomola Moshoeu.
The North West High Court sentenced them to 18 and 23 years in prison respectively.
Their lawyers directly petitioned the Supreme Court of Appeal to overturn the conviction and sentence.
Doorewaard and Schutte claimed Moshoeu jumped out of a moving van after they caught him stealing sunflower heads at a farm in Coligny.
The 16-year-old's death sparked mass violent protests in 2017, with angry residents torching homes, trucks and looting shops there.