Judge Thokosile Masipa is due to give her verdict at the murder trial of Oscar Pistorius in Pretoria, South Africa.
The 27-year-old Paralympic champion faces 25 years in jail if found guilty of premeditated murder.
Oscar Pistorius denies intentionally killing his girlfriend Reeva Steenkamp on Valentine’s Day of 2013, saying he thought there was an intruder.
Judge Thokosile Masipa could also find Oscar Pistorius guilty of culpable homicide, or manslaughter, for which he would face a long jail term.
Oscar Pistorius has pleaded not guilty to all the charges he faces, including two counts of shooting a firearm in public and the illegal possession of ammunition.
During his closing remarks last month, Oscar Pistorius’ lawyer Barry Roux conceded that the athlete should be found guilty of negligence for discharging a firearm in a restaurant – which carries a maximum penalty of five years.
Most of the trial, which began on March 3, 2014, has been televised and attracted worldwide attention.
Before the fatal shooting, Oscar Pistorius was feted in South Africa and known as the “blade runner”.
He had won gold at the London 2012 Paralympic Games and also competed at the Olympics.
The judgement at his trial is likely to be well over 100 pages. The judge will go through each charge, summing up the prosecution and defense cases and analyzing the evidence.
Reeva Steenkamp, a 29-year-old model and law graduate, was hit three times by bullets shot through a toilet door by Oscar Pistorius at his home in the capital, Pretoria, in the early hours of February 14, 2013.
Oscar Pistorius denies the prosecution’s allegation that the couple – who had been dating for three months – had rowed.
The athlete said he thought Reeva Steenkamp was still in the bedroom when he heard a noise in the bathroom, which he believed to be an intruder.
The prosecution have tried to characterize Oscar Pistorius as a “hothead”, while his defense team have portrayed him as having a heightened response to perceived danger because of his disability and background.
In July, a psychiatric report requested by the judge said Oscar Pistorius had post-traumatic stress disorder but no mental illness that could prevent him being held criminally responsible for his actions.