At the trial's conclusion, Judge Thokozile Masipa will have to decide whether Pistorius genuinely made a mistake or killed Steenkamp intentionally.
If she does not believe the athlete thought there was an intruder, she will find him guilty of murder and sentence him to at least 15 years in prison and possibly life. South Africa does not have the death penalty.
If Masipa accepts that Pistorius did not know Steenkamp was the person he was shooting at, she could find him guilty of culpable homicide, a lesser charge than murder, or acquit him, according to CNN legal analyst Kelly Phelps.
A verdict of culpable homicide would leave the sentence at Masipa's discretion.