Lawyer suggests 'excessive self-defence' in fatal stabbing

A court has been told it cannot rule out the possibility a 16-year-old girl was "goaded" or acted in "excessive self-defence" when she fatally stabbed her father.

The now-19-year-old, who cannot be named, stood trial in South Australia's Supreme Court this month after she pleaded not guilty to murdering her father at his northern suburbs of Adelaide home in the early hours of Boxing Day, 2022.

She has pleaded guilty to manslaughter, but it was not accepted by the Director of Public Prosecutions.

The trial, by judge alone, previously heard the teenage girl had been drinking throughout Christmas Day and became "significantly intoxicated" before being taken home where she slept for a few hours.

Prosecutor Karen Ingleton said, upon waking up in the early hours of December 26, the teenage girl was "angry" and "swearing" before she allegedly picked up "a knife from the sink and plunge[d] it straight into [her father's] chest".

In his final address to the court, lawyer Robert Walker said the prosecution had not proved beyond a reasonable doubt that his client intended to kill her father, and there were "other possibilities" as to what happened.

He said her excessive alcohol consumption led her to make an "impulsive, ill-thought-through decision without thought of the consequences".

Mr Walker said the court could not exclude the possibility the girl was "goaded" by her father to stab him.

"Your Honour heard evidence that he said from time to time 'do it' when she threatened to stab him," he said.

Mr Walker said his client may have also acted in "excessive self-defence".

"The evidence shows that whether she did right or wrong, [her father] physically restrained [her] on the couch and said that if police didn't arrive, he would kill her," he said.

"There's evidence from there that she didn't seek him out but that he sought her out.

"She was backed into a corner in the kitchen.

"In an intoxicated state, she could perceive herself as being under threat by the man who physically restrained her and threatened to kill her, and under threat because she was 16 years old. She was 20cm shorter than [her father]."

Justice Rachael Gray will hand down her verdict at a later date.