The judge who will decide the fate of Oscar Pistorius will today finish hearing defence and prosecution witnesses after painful courtroom scenes.

Pistorius was found guilty of the culpable homicide of Reeva Steenkamp, whom he shot through a bathroom door after mistaking her for an intruder. He faces up to 15 years in jail, but could be given a community sentence.

Judge Thokozile Masipa has heard from lawyers and witnesses in pre-sentencing hearings during the last few days in what is almost a re-run of the trial. The process is required in South African law but has been profoundly distressing for the families on both sides.

Pistorius has spoken of his strong Christian faith and how it has helped him during the last few months. His lawyer Barry Roux has described him as a 'victim' and has urged Judge Masipa to show humanity in sentencing him. He said that a mental health evaluation showed that he was not a risk to society and argued that a community-based sentence would be more appropriate than prison. Roux backed up his pleas with references to other culpable homicide cases in which the perpetrators did not go to prison. In a strikingly similar case, a man heard a bathroom window being opened in his home and fired shots into a door, only to discover that his wife was behind it.

Two defence witnesses have also said that Pistorius be placed under house arrest for three years. His personal psychologist, Dr Lore Hartzenberg, has described his remorse and pain as genuine. Other witnesses have highlighted failings in South Africa's prison system.

However, prosecuting lawyer Gerrie Nel has described a community sentence as "shockingly inappropriate", saying: "If the court sentence is too light, and society loses trust in the court, they will take the law into their own hands. That's what the court has to guard against."

Reeva Steenkamp's cousin Kim Martin said Pistorius "needs to pay for what he has done", telling the court: "We need a message to society that you can't do this." She said: "My family are not people who are seeking revenge, we just feel that to shoot somebody behind a door that is unarmed, that is harmless, needs sufficient punishment."

The courtroom has witnessed dramatic scenes during the sentencing hearing. Earlier this week Pistorius' sister Aimee was allegedly threatened by Mikey Schultz, whom she said mouthed an expletive at her as she walked past him. Ms Pistorius burst into tears. Schultz is said to be a friend of Mark Batchelor, a former footballer who alleged that Oscar Pistorius threatened to break his legs in a row over a former girlfriend.

The defence and prosecution hearings will finish today and it is believed that the sentence itself may be delivered early next week.