Just over three years after he fatally shot and killed his girlfriend, South African Olympic sprinter Oscar Pistorius has reached the end of the road: A curt, one-page order from the

highest court in the country denied him a chance to appeal his murder conviction.

Pistorius will appear in Pretoria’s High Court on March 18 to face sentencing after the Constitutional Court dismissed his appeal “for lack of prospects of success.”

The prosecution will argue for a sentence of at least 15 years at next month’s hearing, a spokesman for the National Prosecuting Authority told local news media. It had argued in papers filed to the Constitutional Court that it was not in the interests of justice for Pistorius to be allowed to appeal the murder conviction.

The athlete shot his girlfriend, Reeva Steenkamp, in the early hours of Valentine’s Day 2013, firing four bullets into the small toilet cubicle where she was standing. He used a cricket bat to break down the door and carried her downstairs, where she died.

Pistorius said during his murder trial that he thought she was an intruder and never intended to kill anyone.

The trial judge, Thokozile Masipa, accepted his story that he believed an intruder was present, and found that because he believed Steenkamp was in the bedroom when he fired, he couldn’t be guilty of murder.

Instead, Masipa said he acted recklessly by firing four times and convicted him of culpable homicide, or negligent killing, and sentenced him to five years in jail.

The prosecution appealed to the Supreme Court of Appeal, which ruled that Masipa’s reasoning in the case was flawed. It convicted Pistorius of murder in a unanimous judgment in December.

The appeals court found that when he fired four times, Pistorius must have been aware that whoever was inside the cubicle might have been killed — regardless of whether he thought the person was an intruder.

Pistorius’ evidence was “vacillating and untruthful” when he testified about what he was thinking when he opened fire, the appeals court found. There were other improbabilities in his testimony, it said.

“At the outset he stated that he fired four shots ‘before I knew it’ and at a time when he was not sure if there was somebody in the toilet. This soon changed to a version that he had fired as he believed that whoever was in the toilet was going to come out to attack him. He later changed this to say that he had never intended to shoot at all,” the appeals court ruling said. “One does not really know what his explanation was for having fired the shots.”

The murder conviction isn’t a finding that Pistorius knew Steenkamp was in the toilet cubicle and intended to kill her. Under a principle in South African law known as dolus eventualis, the identity of the victim was not important, just the fact that Pistorius knew someone was in the cubicle and that firing four shots might kill the person.

“He must have foreseen and therefore did foresee that the person he was firing at behind the door might be fatally injured,” said Judge Eric Leach in December, reading the appeals court judgment.

Pistorius’ achievement as a double amputee who rose to compete in the 2012 Olympics in London inspired the world, which was equally fascinated by his downfall after the shooting. Leach called Steenkamp’s killing “a human tragedy of Shakespearean proportions.”

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