AS she delivered her judgment, Judge Thokozile Masipa cast doubt on witness accounts of hearing a woman's screams - which formed a key part of the prosecution's case.

Ms Masipa said "none of the witnesses had ever heard the accused cry or scream, let alone when he was anxious", apparently acknowledging the possibility of the defence's argument that Oscar Pistorius had been the person heard screaming in a high-pitched voice after discovering he had fatally shot Reeva Steenkamp.

The judge also cited testimony of an acoustics expert called by the defence, saying it cast "serious doubt" on whether witnesses who were hundreds of metres away in their homes - as some state witnesses were - could have differentiated between the screams of a man or a woman.

At one point, Ms Masipa said: "I continue to explain why most witnesses got their facts wrong."

She also said she was disregarding text messages between Ms Steenkamp and Pistorius that had been entered as evidence.

Prosecutors had submitted text messages that showed tension between the pair while the defence submitted messages that indicated mutual affection. That evidence, the judge said, does not prove anything.

"Normal relationships are dynamic and unpredictable most of the time, while human beings are fickle," she said.