Prosecutors were not happy with the culpable homicide conviction and five-year prison sentence handed down by Judge Thokozile Masipa.
"Today, we announce that the NPA filed the application for leave to appeal both the conviction and sentence," it said today in a statement. "The appeal on conviction is based on the question of law."
Pistorius began his prison term on 21 October and will be eligible for release after ten months to complete his sentence under house arrest.
Prosecutor Gerrie Nel had argued that only ten years' imprisonment would satisfy the public.
Some legal experts believe Judge Masipa erred in her interpretation of "murder dolus eventualis", a legal term for when the perpetrator foresees the possibility of his action causing death and persists regardless.
Masipa accepted that a "reasonable" person would have foreseen that shooting into the door of a small toilet cubicle may have killed the person inside. However, she said South African law warns against automatically assuming that because a perpetrator "should have" foreseen the consequences of his actions that he actually did.
The onus was on the state to prove beyond reasonable doubt that Pistorius foresaw the fatal consequences of his actions when he shot at the door, but the judge said the prosecution failed to do so.
A date for the appeal hearing has not yet been set.
June Steenkamp, Reeva's mother, said the family had been "devastated" when Masipa ruled out murder and pre-meditated murder, but said that after sentencing they felt that justice had been done. "We were happy with the sentence – five years is sufficient," she said.
She has since said that she believes the judge made a mistake in failing to convict Pistorius of murder (see below).
Oscar Pistorius: judge made a 'mistake', says Reeva's mother
The mother of Reeva Steenkamp believes the judge who convicted Oscar Pistorius of culpable homicide "made a mistake".
June Steenkamp has spoken out in a number of interviews since Pistorius was sentenced to five years in prison for shooting Reeva on Valentine's Day last year.
Prosecutors announced last week that they will appeal against both the conviction and sentence handed down by Judge Thokozile Masipa.
"I had a lot of trust in her," June said of Judge Masipa in an interview with The Guardian's David Smith. "But I think she did make a mistake."
The Steenkamp family was said to be "devastated" that Judge Masipa ruled out murder and pre-meditated murder, but felt that justice had been done after Pistorius was sentenced to five years in jail.
June said she still did not feel any sense of closure, despite the trial coming to an end last month.
"I've actually been feeling much worse than at the beginning. It's like a realisation that she's not there any more. I sat there every day and I always had things to do, and now it's crystal clear that she's never coming back," said June.
Both she and her husband Barry are tortured by the thought of their daughter's final moments, she said. Reeva was hit in the hip, arm and head through the closed toilet door.
"Imagine what she went through in that toilet, petrified, waiting for God to save her," said June. "That's the worst part. Barry and I both have nightmares and it's always about that, because we always protected her."
June described her daughter as a "perfect child and lovable", saying she could not remember one argument that they had because she was so good.
"We would have loved to have had a little grandchild from her," she tells The Guardian. "We'd love to have had a wedding; her father would love to have taken her down the aisle. And all the great things she was going to do. She could have changed the world. She could have changed South Africa, the way she was going. She had a voice."
Oscar Pistorius: Reeva Steenkamp 'had decided to leave' athlete
Reeva Steenkamp's mother believes her daughter was ready to leave Oscar Pistorius when she was shot dead on Valentine's Day last year.
June Steenkamp, who is publishing a book about her daughter next week, claims that Reeva and Pistorius had not yet slept together and that their relationship was coming to an end.
In an extract from Reeva: A Mother's Story, she says her daughter had "nagging doubts" about their compatibility.
"She had confided to me that she hadn't slept with him," writes June. "They'd shared a bed, but she was scared to take the relationship to that level... She wouldn't want to sleep with Oscar if she wasn't sure. I believe their relationship was coming to an end. In her heart of hearts, she didn't think it was making either of them happy."
June describes Pistorius as "arrogant", "possessive" and "trigger happy" in the book. "It was Reeva's bad luck that she met him, because sooner or later he would have killed someone," she claims.
Pistorius was sentenced to five years in prison for culpable homicide last week. Judge Thokozile Masipa accepted the defence's timeline of events and said Pistorius's version of events – in which he claims he mistook Reeva for a dangerous intruder – could be "reasonably, possibly true".
But June does not accept Pistorius's story. "He said pulling the trigger was 'an accident'. What? Four times an accident?" she says. "He said Reeva did not scream, but she would definitely have screamed. I know my daughter and she was very vocal."
June speculates that one of them might have received a Valentine's Day message from another admirer and that might have sparked a row – although no such message was brought up in court. She believes Pistorius shot Reeva in a jealous rage and then shot three more bullets to ensure she could not tell the world what really happened.
"Her clothes were packed. There is no doubt in our minds: she had decided to leave Oscar that night," she claims.
The Timeshas paid to serialise June's book and also interviewedher following Pistorius's sentencing. Here is what else she had to say:
Reaction to verdict
The Steenkamp family were "devastated" when Judge Masipa first ruled out murder and pre-meditated murder. "I felt very, very disappointed. Heartsore, actually, and exhausted," says June. "It was the worst of double whammies – to lose our daughter and then to see her violent death officially deemed an accident."
Reaction to sentence
June says she felt "so much better" after the sentencing and believed that Judge Masipa gave a "balanced consideration" of the mitigating and aggravating arguments. "We feel justice has been done. We were happy with the sentence – five years is sufficient," she says. However, she has noted that no sentence could ever provide closure for her family. "Nothing can – unless someone can magic Reeva back."
Feelings towards Oscar
June says she has forgiven Pistorius "in the Christian sense" and has "no feelings" towards him, good or bad. "We just want the truth and he is the only person who can fill in the missing blanks of what happened that night," she says. Both June and her husband Barry would like to sit down in private with the athlete. June says she has "no hate" in her heart for Pistorius's family either and feels sympathy for what they have gone through.
Oscar Pistorius: prosecution has 'appetite' to appeal
South Africa's National Prosecuting Authority is considering whether to appeal against Oscar Pistorius's culpable homicide verdict.
The athlete was yesterday sentenced to five years in prison for killing his girlfriend Reeva Steenkamp on Valentine's Day last year and has spent his first night in Kgosi Mampuru prison in Pretoria.
Pistorius's defence lawyers suggested that he could serve just ten months in jail, a period only slightly longer than the duration of his trial.
His family told reporters that he did not intend to lodge an appeal and would "embrace" the opportunity to "pay back to society".
The NPA, however, has indicated that it has an "appetite" to appeal. "We have always stated first and foremost that we were disappointed with the conviction," NPA spokesman Nathi Mncube told reporters. "But we do find solace in the fact the accused will serve some time in prison."
Both sides have the opportunity to appeal within 14 days. Mncube said the NPA would use this time to consider whether the facts and the law allowed them to appeal, and suggested that the state would appeal the verdict, but not the sentence.
"It is not a straightforward matter because there is law we have to consider, to ensure that if we do take the matter to appeal, we are able to support the decision. But hopefully we will able to do so," he said.
Some South African lawyers questioned whether Judge Thokozile Masipa had erred in clearing Pistorius of murderlast month.
In explaining why she could only convict him on culpable homicide, Masipa acknowledged that a "reasonable" person with Pistorius's disabilities would have foreseen that shooting into the door may have killed the person inside. However, she said South African law warns against automatically assuming that because a perpetrator "should have" foreseen the consequences of his actions that he actually did.
She said that the prosecution had failed to prove beyond reasonable doubt that Pistorius foresaw the fatal consequences of his actions when he shot at the door, meaning she could not convict him on a murder charge.
Oscar Pistorius: is five years in prison justice for Reeva?
After an emotional seven-month trial, Oscar Pistorius was calm and composed today as Judge Thokozile Masipa sentenced him to five years in prison – but outside the courtroom, reactions were more extreme.
The defence team said it expects the athlete to serve only ten months behind bars and the remainder under house arrest, while the prosecution believe he will have to serve at least 20 months.
The prospect of Pistorius leaving jail within a year provoked outrage on Twitter, with the hashtag #Nojustice trending worldwide.
Sky Newsreporter Robert Nisbet said the overwhelming reaction on the streets of Pretoria was also negative. "He took the soul of another person. How can that be right?" one man said outside the court.
But Reeva Steenkamp's mother June says justice has been served. She told reporters "it doesn't matter" that Pistorius could be out of prison in ten months. "He's going to pay something," she said.
Pistorius's family also said they were satisfied with the sentence and added that the athlete will "embrace this opportunity to pay back to society".
Professor Stephen Tuson, of Wits School of Law, told News24it would be "inadvisable" for Pistorius to appeal against the sentence as he "got off lightly" for culpable homicide.
Masipa sentenced the athlete to a maximum imprisonment of five years for killing Reeva and a concurrent three-year prison sentence, suspended for five years, for discharging a firearm in a Johannesburg restaurant in January 2013.
In The Independent, Chris Maume says Masipa "might have shown mercy, but she has delivered perfect justice". A non-custodial sentence would have "sent the wrong message" that if you are famous enough, you can get away with manslaughter, while a longer hail sentence "would have felt like grandstanding", says Maume.
But in The Guardian, Simon Jenkins thinks Pistorius should not be going to jail at all. Masipa's argument was "meticulously reasoned", says Jenkins, but "beyond the cause of consistency, imprisoning Pistorius can serve no purpose".
He describes imprisonment as "brutalism" and says no one will be more or less deterred by the length of his sentence.
"Finding why he behaved as he did, and working to prevent others doing likewise, would be the most useful outcome of his crime. That is unlikely to happen in a prison."
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