A judge “overemphasised” Oscar Pistorius’s disability and was far too lenient on the double-amputee athlete, prosecutors said on Friday as they tried to convince a South African court to more than double his prison sentence from six to 15 years for the murder of his girlfriend Reeva Steenkamp.

“Murder is murder,” chief prosecutor Andrea Johnson told a five-judge panel at the Supreme Court of Appeal. She asked them to overturn Pistorius’s initial sentence and give him the prescribed minimum of 15 years. There is no death penalty in South Africa.

If the court agrees with prosecutors that he deserves a harsher sentence, Pistorius, now 30, could remain in prison until after he turns 40.

The judges did not deliver a decision on Friday. Typically, Supreme Court judges take a couple of weeks before the senior judge returns to read out the decision, which is made through a simple majority.

Nearly five years after the once-admired Olympic and Paralympic runner first appeared in court for shooting Steenkamp multiple times through a closed toilet door at his home, Pistorius’s fate is still not certain.

He was not present at Friday’s hearing as he serves his sentence at a prison near Pretoria. He has served more than a year of his six-year term. Steenkamp’s mother, June Steenkamp, did attend. Speaking outside the courthouse, her lawyer said the Steenkamp family supported prosecutors’ attempt to get a longer sentence.

Prosecutors had two arguments to make to the court. First, they needed to apply for permission to appeal Pistorius’s sentence. They were asked by the judges to also present their arguments for why, if their appeal is allowed, his sentence should be increased.

This is the second time prosecutors have gone to the Supreme Court in the central city of Bloemfontein to challenge a decision by Judge Thokozile Masipa, who presided over Pistorius’s trial.

In 2015, prosecutors successfully appealed against Ms Masipa’s judgement that Pistorius was not guilty of murder. The court overturned Ms Masipa’s verdict of culpable homicide – or manslaughter – and convicted Pistorius of murder.

Legal analysts say, however, it is more difficult to get the court to change a sentence.

After the manslaughter conviction was overturned, Ms Masipa sentenced Pistorius to six years in prison for murder, a term just one year longer than her original sentence for manslaughter. Prosecutors called that sentence “shockingly” light.

Judges can deviate from prescribed minimum sentences if there are compelling circumstances. The prosecution says there were no compelling reasons.

“What we are saying is the court exercised its discretion inappropriately,” prosecutor Ms Johnson said, calling the six-year sentence “unjust.”

She said Pistorius still had not shown “genuine remorse” for killing Steenkamp and that Ms Masipa put the athlete’s personal circumstances and his disability ahead of the need for “retribution” when she sentenced him.

Pistorius claimed he mistook Steenkamp for a dangerous intruder hiding in his bathroom in the pre-dawn hours of Valentine’s Day 2013 when, without his prosthetic legs on, standing on his stumps and feeling vulnerable, he shot four times through the cubicle door.

In pictures: Oscar Pistorius trial Show all 90 1 /90 In pictures: Oscar Pistorius trial In pictures: Oscar Pistorius trial Oscar Pistorius arrives at court Oscar Pistorius arrives at court prior to another day of cross examination during his ongoing murder trial in Pretoria In pictures: Oscar Pistorius trial Oscar Pistorius arrives at court Oscar Pistorius is greeted by the "Support for Oscar" Facebook group members as he arrives at the Pretoria High Court In pictures: Oscar Pistorius trial Prosecutor Gerrie Nel in court Prosecutor Gerrie Nel walks past a courtroom reconstruction of the toilet in which Reeva Steenkamp was shot and killed during Oscar Pistorius' murder trial at the high court in Pretoria In pictures: Oscar Pistorius trial Prosecutor Gerrie Nel in court Prosecutor Gerrie Nel gestures as he explains a possible scenario into how Oscar Pistorius might have fired on girlfriend Reeva Steenkamp in court in Pretoria In pictures: Oscar Pistorius trial The door through which Reeva Steenkamp was shot used as evidence in court The door through which Reeva Steenkamp was shot used as evidence and displayed during the Oscar Pistorius murder trial at the high court in Pretoria In pictures: Oscar Pistorius trial Oscar Pistorius leaves court Oscar Pistorius leaves the high court in Pretoria In pictures: Oscar Pistorius trial June Steenkamp in court June Steenkamp, mother of Reeva, is comforted by unidentified relative after her dead daughter's picture was shown on screen during the trial of Oscar Pistorius at the North Gauteng High Court in Pretoria In pictures: Oscar Pistorius trial Aimee Pistorius and Lois Pistorius in court Sister of Oscar Pistorius, Aimee Pistorius (L) and aunt Lois Pistorius (R) listen as Oscar Pistorius testifies in court in Pretoria In pictures: Oscar Pistorius trial Gina Myers in court Gina Myers, Reeva Steenkamp's best friend, is overcome with emotion as she listens to Oscar Pistorius' testimony in the Pretoria High Court In pictures: Oscar Pistorius trial Aimee Pistorius cries in court Aimee Pistorius (R), sister of Oscar Pistorius, cries as she hears her brother tell his story of the events on the night he killed Reeva Steenkamp during his ongoing murder trial in Pretoria In pictures: Oscar Pistorius trial June Steenkamp in court June Steenkamp hides her face as she listens to Oscar Pistorius' testimony in the Pretoria High Court In pictures: Oscar Pistorius trial Arnold and Lois Pistorius cry in court Arnold and Lois Pistorius overcome with emotion as they listen to their nephew Oscar's testimony in the Pretoria High Court In pictures: Oscar Pistorius trial Oscar Pistorius in court Oscar Pistorius reacts as he listens to evidence by a pathologist during his trial in court in Pretoria In pictures: Oscar Pistorius trial Oscar Pistorius in court Oscar Pistorius reacts during his trial for the murder of his girlfriend Reeva Steenkamp at the North Gauteng High Court in Pretoria In pictures: Oscar Pistorius trial Gerrie Nel speaks in court State Prosecutor Gerrie Nel speaks as he cross-examines the pathologist during the trial of Oscar Pistorius in court in Pretoria In pictures: Oscar Pistorius trial Oscar Pistorius in court Oscar Pistorius puts his hands to his head while he sits during his trial at the North Gauteng High Court in Pretoria In pictures: Oscar Pistorius trial Oscar Pistorius in court Oscar Pistorius reacts during his trial at the North Gauteng High Court in Pretoria In pictures: Oscar Pistorius trial Oscar Pistorius speaks with relative Oscar Pistorius speaks with a family member during his trial in Court in Pretoria In pictures: Oscar Pistorius trial Aimee Pistorius in court Aimee, sister of Oscar Pistorius, cries as her brother takes the stand to testify at the high court in Pretoria In pictures: Oscar Pistorius trial Carl Pistorius in court Oscar Pistorius' brother Carl Pistorius reacts during Oscar's trial at the high court in Pretoria In pictures: Oscar Pistorius trial June Steenkamp in court June Steenkamp, mother of the late Reeva Steenkamp listens to evidence by a pathologist during the murder trial of Oscar Pistorius in court in Pretoria In pictures: Oscar Pistorius trial Arnold Pistorius and Lois Pistorius in court Uncle Arnold Pistorius and aunt Lois Pistorius look on during the murder trial of Oscar Pistorius at the high court in Pretoria In pictures: Oscar Pistorius trial Oscar Pistorius in court Oscar Pistorius cries as he sits in the dock during his ongoing murder trial in Pretoria In pictures: Oscar Pistorius trial Oscar Pistorius in court Oscar Pistorius sheds tears as he sits in the dock during his ongoing murder trial in Pretoria In pictures: Oscar Pistorius trial Oscar Pistorius in court Oscar Pistorius shedding tears as he sits in the dock during his ongoing murder trial in Pretoria In pictures: Oscar Pistorius trial Oscar Pistorius in court Oscar Pistorius sits in the dock during his murder trial at the high court in Pretoria In pictures: Oscar Pistorius trial Oscar Pistorius in court Oscar Pistorius makes his way to the dock during his ongoing murder trial in Pretoria In pictures: Oscar Pistorius trial Kenny Oldwage questions a witness Kenny Oldwage a member of South African Paralympic athlete Oscar Pistorius' legal team questions a state witness during the ongoing murder trial in Pretoria In pictures: Oscar Pistorius trial Hilton Botha arrives in court Hilton Botha, former lead detective in the Oscar Pistorius murder case, arrives ahead of Pistorius's trial at the North Gauteng High Court in Pretoria In pictures: Oscar Pistorius trial A member of the African National Congress Women's League outside the court A member of the African National Congress Women's League holds a mobile phone with a picture of Reeva Steenkamp outside the high court in Pretoria In pictures: Oscar Pistorius trial Pistorius cries during his trial Oscar Pistorius cries during his trial at the North Gauteng High Court, Pretoria In pictures: Oscar Pistorius trial Pistorius is comforted by relatives Oscar Pistorius is comforted by relatives as he sits in the dock during court proceedings at the North Gauteng High Court in Pretoria In pictures: Oscar Pistorius trial Pistorius is comforted by relatives Oscar Pistorius is hugged by his aunt Lois in the North Gauteng High Court in Pretoria In pictures: Oscar Pistorius trial Pistorius in the dock Oscar Pistorius holds his head in his hands in the dock during cross examination of a witnesses in court in Pretoria In pictures: Oscar Pistorius trial Pistorius leaves court Oscar Pistorius is photographed as he leaves at the end of his trial for the murder of his girlfriend Reeva Steenkamp, at the North Gauteng High Court in Pretoria In pictures: Oscar Pistorius trial Oscar Pistorius and Aimee Pistorius Oscar Pistorius with his sister Aimee Pistorius during the murder trial at the high court in Pretoria In pictures: Oscar Pistorius trial Photographs of Pistorius taken after the shooting Pistorius from the waist up, with a tattoo visible on his back, and blood on his left arm In pictures: Oscar Pistorius trial Photographs of Pistorius taken after the shooting Photographs of Pistorius taken soon after fatal shooting of Reeva Steenkamp were shown in court. The athlete's prosthetic legs are splattered with blood In pictures: Oscar Pistorius trial Pistorius' watch collection with blood marks on it A photograph of Pistorius' watch collection with blood marks on it. One of the watches went missing the night police searched the house after Reeva Steenkamp was shot on Valentine's Day. In pictures: Oscar Pistorius trial Pistorius's bedroom with the duvet on the floor A close up of Pistorius's bedroom, with the duvet on the floor. Pistorius argues he woke up to bring a fan from his balcony when he heard noises coming the bathroom In pictures: Oscar Pistorius trial Pistorius covers his head with a notebook as he listens to forensic evidence Oscar Pistorius covers his head with a notebook as he listens to forensic evidence during his trial in court in Pretoria In pictures: Oscar Pistorius trial Pistorius puts his hands to his head while he sits in court Oscar Pistorius puts his hands to his head as he listens to forensic evidence during his trial in court in Pretoria In pictures: Oscar Pistorius trial Pistorius reacts while listening evidence in court Oscar Pistorius reacts during his murder trial at the North Gauteng High Court in Pretoria In pictures: Oscar Pistorius trial Pistorius places his head in his hands Oscar Pistorius places his head in his hands as he listens to the cross examination during his trial in court in Pretoria In pictures: Oscar Pistorius trial Pistorius during his continuous trial Oscar Pistorius sits in the dock during his murder trial at the North Gauteng High Court in Pretoria In pictures: Oscar Pistorius trial Lt Col JG Vermeulen demonstrates the effect of hitting of a bathroom door Lt Col JG Vermeulen demonstrates the effect of hitting of a bathroom door with a cricket bat during the trail of Oscar Pistorius in the North Gauteng High Court in Pretoria In pictures: Oscar Pistorius trial Lt Col JG Vermeulen recreates a possible scenario at Oscar Pistorius home Lt Col JG Vermeulen recreates a possible scenario at Oscar Pistorius home when he shot his girlfriend Reeva Steenkamp In pictures: Oscar Pistorius trial Pistorius's defence team questions forensic evidence Pistorius's defence team questions forensic evidence suggesting the athlete was wearing his prosthetic legs when he hit the lavatory's door with a cricket bat In pictures: Oscar Pistorius trial State prosecutor Gerrie Nel speaks in court State prosecutor Gerrie Nel makes a point during the trial of Oscar Pistorius at the North Gauteng High Court in Pretoria In pictures: Oscar Pistorius trial Pistorius speaks with his legal team Oscar Pistorius speaks with a member of his legal team prior to a hearing of his trial at the North Gauteng High Court in Pretoria In pictures: Oscar Pistorius trial Pistorius sits in court Oscar Pistorius sits with hands on his head at the court dock during the ongoing murder trial at the North Gauteng High Court in Pretoria In pictures: Oscar Pistorius trial Pistorius in court during ongoing trial Oscar Pistorius sits in the dock on another day of his trial at the North Gauteng High Court in Pretoria In pictures: Oscar Pistorius trial State prosecutor Gerrie Nel in court State prosecutor Gerrie Nel takes part in Oscar Pistorius' ongoing murder trial at the North Gauteng High Court in Pretoria In pictures: Oscar Pistorius trial Pistorius arrives in court The accused arrives at the Pretoria High Court in Pretoria In pictures: Oscar Pistorius trial Pistorius cries in court Oscar Pistorius cries as he listens to cross questioning about the events surrounding the shooting death of his girlfriend Reeva Steenkamp, in court during his trial in Pretoria In pictures: Oscar Pistorius trial Pistorius cries in court Oscar Pistorius cries as he chats to his lawyer Barry Roux during his trial for the murder of his girlfriend Reeva Steenkamp, at the North Gauteng High Court in Pretoria In pictures: Oscar Pistorius trial Pistorius on the sixth day of his trial Oscar Pistorius holds his hands to his face as he sits in the dock during day 6 of his murder trial at the High Court in Pretoria In pictures: Oscar Pistorius trial Pistorius sits in court Oscar Pistorius is pictured with hands on his head during a hearing on the sixth day of his murder trial In pictures: Oscar Pistorius trial Relatives of Reeva Steenkamp in court Relatives and friends of Reeva Steenkamp, Gina Meyers (C) and her mother Desiree (R) attend a hearing of Oscar Pistorius on the sixth day of his trial In pictures: Oscar Pistorius trial Pistorius arrives in court Oscar Pistorius arrives at the Pretoria High Court in Pretoria In pictures: Oscar Pistorius trial Security guard Pieter Baba testifies Security guard Pieter Baba testifies the murder trial of South African Paralympic star Oscar Pistorius at the high court of Pretoria In pictures: Oscar Pistorius trial Pistorius family in court Aimee Pistorius, sister of Olympic and Paralympic track star Oscar, rests her head on an unidentified woman's shoulder during the fifth day of his trial for the murder of his girlfriend Reeva Steenkamp at the North Gauteng High Court in Pretoria In pictures: Oscar Pistorius trial Oscar Pistorius listens as witness testifies Oscar Pistorius puts his hands to his head while a witness testifies and speaks about the morning of the shooting of his girlfriend Reeva Steenkamp In pictures: Oscar Pistorius trial Oscar Pistorius cries Oscar Pistorius cries while a witness testifies during the fourth day of his trial for the murder of his girlfriend Reeva Steenkamp at the North Gauteng High Court in Pretoria In pictures: Oscar Pistorius trial Oscar Pistorius looks at notes Oscar Pistorius looks at notes during the fourth day of his trial for the murder of his girlfriend Reeva Steenkamp at the North Gauteng High Court in Pretoria In pictures: Oscar Pistorius trial Oscar Pistorius on the second day of his trial Covering his ears, on empty benches, Oscar Pistoius gestures after arriving at the North Gauteng High Court in Pretoria In pictures: Oscar Pistorius trial Oscar Pistorius reads defense paperwork Oscar Pistorius looks at his defense team paperwork during a break on the second day of his trial at the North Gauteng High Court in Pretoria In pictures: Oscar Pistorius trial Members of the media during the trial Members of the media work during a break in proceedings on the second day of the murder trial of South African Paralympic athlete Oscar Pistorius at the North Gauteng High Court in Pretoria In pictures: Oscar Pistorius trial Oscar Pistorius during trial Oscar Pistorius looks on inside the Pretoria High Court In pictures: Oscar Pistorius trial Chief investigating officer Lieutenant General Vineshkumar Moonoo during the trial Chief investigating officer Lieutenant General Vineshkumar Moonoo gestures during the second day of the murder trial of South African Paralympic athlete Oscar Pistorius at the North Gauteng High Court in Pretoria In pictures: Oscar Pistorius trial Oscar Pistorius leaves court Oscar Pistorius leaves North Gauteng High Court during the lunchtime break as he faces trial accused of the murder of his girlfriend Reeva Steenkamp in Pretoria In pictures: Oscar Pistorius trial Oscar Pistorius in court Oscar Pistorius at the Pretoria High Court in Pretoria In pictures: Oscar Pistorius trial Oscar Pistorius and Barry Roux in court Oscar Pistorius and Barry Roux at the Pretoria High Court in Pretoria In pictures: Oscar Pistorius trial Advocate Barry Roux speaks in court Advocate Barry Roux at the Pretoria High Court in Pretoria In pictures: Oscar Pistorius trial Oscar Pistorius in court Oscar Pistorius at the Pretoria High Court in Pretoria In pictures: Oscar Pistorius trial Oscar Pistorius in court Oscar Pistorius walks at the Pretoria High Court as Reeva Steenkamp's mother looks on In pictures: Oscar Pistorius trial June Steenkamp in court Reeva Steenkamp's mother looks on inside the Pretoria High Court In pictures: Oscar Pistorius trial Lois, Arnold and Aimee Pistorius in court Lois, Arnold and Aimee Pistorius at the Pretoria High Court in Pretoria In pictures: Oscar Pistorius trial Carl, Aimee and Lois Pistorius in court Carl, Aimee and Lois Pistorius speaking with a member of his legal team at the Pretoria High Court in Pretoria In pictures: Oscar Pistorius trial Carl Pistorious in court Carl Pistorious, the brother of South African Paralympic athlete Oscar Pistorius, leaves the courtroom during a lunch recess at the High Court in Pretoria In pictures: Oscar Pistorius trial Prosecutor Gerrie Nel Prosecutor Gerrie Nel reads out the charges on the opening day of proceedings in the High Court in Pretoria In pictures: Oscar Pistorius trial Pretoria news A newspaper vendor sells the Pretoria News as the Oscar Pistorius trail starts at North Gauteng High Court in Pretoria. Olympic and Paralympic athlete Oscar Pistorius is accused of murdering his girlfriend Reeva Steenkamp. Pistorius denies the allegation claiming he mistook Steenkamp for an intruder inside their home on Valentines Day 2013 In pictures: Oscar Pistorius trial June Steenkamp in court June Steenkamp (L), mother of the murdered Reeva Steenkamp, sits in court ahead of the trial of Olympic and Paralympic track star Oscar Pistorius at the North Gauteng High Court in Pretoria In pictures: Oscar Pistorius trial June Steenkamp arrives in court June Steenkamp (C), the mother of Reeva Steenkamp, arrives at North Gauteng High Court for the trial of Oscar Pistorius in Pretoria In pictures: Oscar Pistorius trial June Steenkamp arrives in court June Steenkamp (R), the mother of Reeva Steenkamp, arrives at North Gauteng High Court for the trial of Oscar Pistorius in Pretoria In pictures: Oscar Pistorius trial Carl Pistorius arrives in court Police try to hold back the media as Carl Pistorius, the brother of Oscar Pistorius, arrives at North Gauteng High Court in Pretoria In pictures: Oscar Pistorius trial Media outside the court in Pretoria Bewildered media stand outside North Gauteng High Court as Oscar Pistrious slips into court through another door to face trial accused of the murder of his girlfriend Reeva Steenkamp in Pretoria In pictures: Oscar Pistorius trial Daily News front page day after the shooting Oscar Pistorius was arrested in South Africa in the shooting of Reeva Steenkamp In pictures: Oscar Pistorius trial Oscar Pistorius and Reeva Steenkamp Oscar Pistorius and Reeva Steenkamp at the Feather Awards in 2012 in Johannesburg In pictures: Oscar Pistorius trial Reeva Steenkamp Reeva Steenkamp who was shot dead on the Valentine's Day 2013

Ms Masipa’s initial sentence was appropriate in the circumstances, Pistorius’s defence lawyers said, and his disability was not exaggerated. Pistorius had both his legs amputated below the knee when he was a baby because of a congenital condition.

“Of course his disability is mentioned, but it can’t not be mentioned,” defence lawyer Kelly Phelps said. “It is one of the factors of this case. We can’t magic away his disability.”