(CNN) -- Oscar Pistorius has been found guilty of the murder of Reeva Steenkamp, after South Africa's Supreme Court overturned the previous conviction of culpable homicide.
Judge Eric Leach ruled Thursday that paralympic gold medalist should have foreseen that his firing of the gun would have killed whoever was behind the door, regardless of whether he thought it was Steenkamp or an intruder.
Pistorius shot girlfriend Reeva Steenkamp, a model, four times through a locked toilet door on Valentine's Day 2013, saying he mistook her for an intruder.
His jail term is yet to be decided but he faces up to 15 years in prison.
Pistorius was allowed to move from prison in October, where he served a year of his original five-year sentence, to house detention.
Dolus Eventualis
The judge called the circumstances surrounding Steenkamp's death "a human tragedy of Shakespearean proportions."
The ruling rested over the concept of "dolus eventualis," or whether Pistorius should have foreseen whether his actions would lead to death.
"All the shots fired through the door would almost inevitably have struck the person behind it. There would be effectively no place to hide," Leach said.
He called called Pistorius' testimony about his actions when firing the gun "unacceptable," "vacillating" and "contradictory."
Prosecutors argued that the 29-year old -- known as the "Blade Runner" in a reference to the prosthetic legs he uses when he races -- intentionally killed Steenkamp following an argument, and appealed for his sentence be changed to murder on the basis that he knew he could kill the person behind the door by firing his gun.
Leach stated that although Pistorius had genuine but erroneous beliefs that his life was in danger when he fired the shots, he should have acted more rationally.
He never fired a warning shot, and shot not once but four times.
"The identity of victim is irrelevant to his guilt," he said.
Steenkamp's family members were present, keeping a stony-faced throughout the court proceeding, but hugged after hearing the verdict.
A jail official told CNN that the athlete didn't receive any special treatment, but he was the first double-amputee prisoner in their detention and required protection.
The-CNN-Wire
™ & © 2015 Cable News Network, Inc., a Time Warner Company. All rights reserved.