Oscar Pistorius
How long could Oscar Pistorius spend in prison if not cleared of all charges? Getty

Judgement day for Oscar Pistorius is nigh: six months after the trial began judge Thokozile Masipa will soon deliver her verdict in the world's biggest court case.

Pistorius's fall from grace has been dizzying: an athlete at the top of his game, venerated the world over for heroically overcoming his disability. Gunning down the woman he claims to have loved, on Valentine's Day of all days - you couldn't write it.

Here is a rundown of the charges Pistorius faces and an estimation of how long the 27-year-old could spend locked up in prison.

Guilty of Murder: 25 years

This charge carries a tariff of 25 years in prison. There was some surprise among court watchers in South Africa that the prosecution in this case pushed for a murder charge ahead of the trial. But Gerrie Nel's savage interrogation of Pistorius and others left nobody in doubt of the prosecution's aim at the jugular.

So excoriating was Nell's cross-examination that an investigation was even launched into whether he had breached Pistorius's human rights by reducing the track star to a blubbering wreck on at least three occasions.

Guilty of Culpable homicide: up to 15 years

This is similar to manslaughter in the British justice system. Pistorius could be found guilty of culpable homicide if he is cleared of pre-meditated murder by judge Masipa. This would be standard manoeuvre in many cases of unlawful killing in the absence of outright murder - but this is not a standard case.

Illegal ammo: up to 15 years

This charge may appear somewhat innocuous next to murder, but it could land Pistorius in clink for as long as being guilty of culpable homicide.

Rather sensationally, when Pistorius's team asked his own father to provide an alibi for a stash of ammo for which the runner has no license, his own father said "no".

Guilty of firing guns in public: up to five years (x2)

Pistorius is accused of two firearms charges, each of which carries a five year sentence.

The first relates to an incident at a restaurant in Johannesburg called Tasha's, just one month before Steenkamp was blasted to death.

The second firearms charge relates to Pistorius allegedly firing a gun through the roof of a vehicle in late 2012.

Plenty of potential bird on the rap sheet for Pistorius then - but can South Africa stomach seeing another of its heroes languish in jail?