By James Macharia

JOHANNESBURG (Reuters) - South African paralympic gold medalist Oscar Pistorius will be sentenced to jail on Wednesday for the murder of his girlfriend Reeva Steenkamp in 2013, but for how long depends largely on how the judge will weigh the role of his disability in the killing.

Pistorius, 29, was found guilty of murdering Steenkamp by an appeals court last December. He had initially received a five-year sentence for a manslaughter conviction in 2014, a ruling that was decried as too lenient by women's groups.

The athlete had the lower part of his legs amputated when he was a baby, and his lawyers have argued that his physical disability and mental stress should be considered as mitigating circumstances to reduce his sentence.

During the hearings, his defense lawyer asked Pistorius to walk on his stumps to show the difficulty he faced dealing with the threat of an intruder.

But the state says he has shown no remorse and has called for him to receive no less than the minimum sentence for murder.

Some rights groups have said Pistorius, a wealthy white man and international celebrity, has received preferential treatment compared to others without his status or wealth.

Pistorius was freed from prison last October after almost a year behind bars to serve out the remainder of his term under house arrest on his uncle's house in a wealthy suburb of Pretoria.

In December however, the Supreme Court upgraded his conviction to murder on appeal.

The original trial judge, Thokozile Masipa, will deliver the sentence at the Pretoria High Court.

Johannesburg-based lawyer and legal analyst Ulrich Roux said Masipa would have to balance any mitigating circumstances against the seriousness of his crime.

"For her it's a delicate balancing act," said Roux, adding that either the defense or prosecution could mount a legal challenge if they felt that the sentence was lenient or harsh.

In a television interview with British broadcaster ITV aired in June, his first since the shooting, an emotional Pistorius said that Steenkamp would want him to go free.

"I don’t want to go back to jail. I don’t want to have to waste my life sitting there," Pistorius told ITV, statements which caused an uproar on social media.

Manelisi Wolela, a spokesman at the Department of Correctional Services, said Pistorius would be taken to jail immediately after the sentencing.

(Editing by Raissa Kasolowsky)