JOHANNESBURG (Reuters) - South African prosecutors will appeal against the culpable homicide verdict and five-year jail sentence passed on Oscar Pistorius last week after public and legal criticism of the judge's decision to absolve the track star of murder.
The Olympic and Paralympic athlete, whose lower legs were amputated as a baby, killed his girlfriend on Valentine's Day last year by firing four 9mm rounds into the locked door of a toilet cubicle in what he said was the mistaken belief an intruder was hiding behind it.
The announcement of the appeal came on Monday in a Twitter statement from Nathi Mncube, spokesman for the National Prosecuting Authority (NPA): "Oscar Pistorius judgment, NPA will be appealing both the conviction and sentence."
Mncube confirmed the appeal in an email to Reuters but gave no further details.
During the sensational seven-month trial, the state failed to convince judge Thokozile Masipa of Pistorius' intent to kill when he fired, leading to his conviction for negligent killing - culpable homicide - and a five-year jail term last week.
However, Masipa's decision to rule out murder was criticized by several legal experts and the Women's League of the African National Congress (ANC) as an erroneous interpretation of 'dolus eventualis', the legal principle by which a person is held accountable for the foreseeable consequences of their actions.
A possible error of law opens the way for an appeal by the state.
Under the principle of 'dolus eventualis', it does not matter whether Pistorius intended to kill Steenkamp, so much as the imaginary person whom he believed to be behind the door.
"We have already sought a legal opinion on the proceedings thus far, especially on the interpretation of the Pistorius judgment and in particular the understanding of the concept of dolus," the ANC Women's League said before Mncube's statement.
"We believe regardless of whom Mr. Pistorius believed was behind the bathroom door on that fateful night, Mr. Pistorius shot to kill and therefore a murder did occur."
James Grant, a professor of criminal law and expert on 'dolus' at Johannesburg's Witwatersrand University, said last week that lead prosecutor Gerrie Nel had asked for his assistance in the event of a possible legal review.
"I have advised that he should appeal and agreed to assist," Grant said on Twitter.
Despite the criticism of Masipa's ruling, some lawyers said her decision was legally sound.
In South Africa, an appeal by the state involves a review of the trial and verdict by a panel of senior judges who only consider the court's interpretation of evidence and matters of law.
They do not initiate a retrial or listen to any new evidence.
If the verdict is overturned and found to be murder, Pistorius could face a much longer stretch behind bars.
He is currently in the hospital wing of the capital's Kgosi Mampuru II prison, formerly known as Pretoria Central.
The vast complex, infamous as the execution site of black activists under South Africa's old white-minority government, is now home to some of its highest-profile criminals, including 'Prime Evil' apartheid death squad leader Eugene de Kock.
Reporting by David Dolan and Ed Cropley; Editing by Joe Brock and Ralph Boulton