PRETORIA, South Africa -- Samantha Taylor, blond with dark eyeliner, cut a slight, nervous figure on the witness stand Friday in Oscar Pistorius' murder trial. Taylor, who began dating the South African Olympic athlete in 2011 at age 17, broke down weeping several times when asked in court about breaking up with him in 2012.
Pistorius stared coldly at his former girlfriend, whom he dropped for model and lawyer Reeva Steenkamp, as she took the witness stand in Pretoria's High Court, smiling uncertainly.
Pistorius killed Steenkamp in the early hours of Valentine's Day last year when he shot her through the closed door of a toilet off the bathroom of their home. He has pleaded not guilty to murder and contends that he mistook her for an intruder.
Taylor's testimony portrayed a young man with a short fuse, who would scream when angered, and who cheated on her. She testified there were several times when he screamed with rage -- at her, her sister, her best friend and another friend.
According to her testimony, he never went anywhere without his pistol: He slept with it either on the bedside table or next to his prosthetic legs. He took it with him on social outings, to friends' houses and elsewhere. When he traveled in a car from Vaal River on Sept. 30, 2012, the gun was on the back seat.
Pistorius fired the gun out of the open sunroof of the car that day after being furious at being stopped by a policeman, who touched the gun, Taylor told the court.
The incident happened when Pistorius' friend Darren Fresco was driving, she said. Police stopped them for speeding and reproved Pistorius for leaving a loaded gun on the seat. As the policeman picked up the gun, Pistorius lost his temper and shouted that he wasn't allowed to touch the gun, Taylor testified.
As they continued driving, he and Fresco complained irritably about the incident, she said, and about 15 minutes later, Pistorius fired the gun out of the open sunroof.
"It was a very, very loud noise," Taylor said. "From my observation, he was angry after being stopped. Thereafter, after firing the shots, they laughed. They found it funny," she said.
Defense attorney Barry Roux said Pistorius would deny ever firing the gun from the car. Taylor insisted that her memory of the incident was very clear.
Pistorius has also pleaded not guilty to two counts of recklessly firing a gun -- one of them relating to the incident described by Taylor and another in a crowded restaurant in January 2013 -- and a charge of having ammunition without a license.
Taylor's testimony contradicted a central point in the defense case: its contention that when Pistorius screams anxiously, he sounds like a woman.
"That is not true," she told the court. "When he screamed, it sounded like a man." The defense has argued that witnesses who testified they heard a woman screaming the night Steenkamp died actually heard Pistorius screaming.
Pistorius, Taylor testified, kept two cellphones and an iPad with him and often used them to send messages in bed at night.
Taylor told the court she used to sleep at Pistorius' house four nights a week. She said there were two breakups with Pistorius. The first time, she said, he dated a woman when he was overseas, so she ended the relationship.
They later resumed their relationship, she said, but they were having problems late in 2012. The relationship ended in early November 2012, when Pistorius "cheated on me with Reeva Steenkamp," she said.
Roux said he would produce emails that showed the relationship had ended by then. Taylor responded that they had been fighting but that the relationship had not ended.
Roux also suggested that Taylor sent an email apologizing to Pistorius for cheating on him. Taylor strongly denied this. She said there had been an "altercation" over a trip she took to Dubai with a man in 2012 when Pistorius was competing in the London Olympics, but at the time she was not the athlete's girlfriend.
In one other piece of testimony that reflects on Pistorius' version of what happened the night he killed Steenkamp, Taylor said Pistorius had once or twice awakened her in the middle of the night to ask her if she heard noises. He then walked around the house with a gun but found nothing, she testified.
The prosecution introduced this testimony because on the night Pistorius killed Steenkamp, after allegedly hearing the noise of a window open, he didn't make an effort to wake Steenkamp, according to his statement at at his bail hearing last year.
Roux asked Taylor if Pistorius was "very scared" of an attack. Taylor responded, "Not necessarily. He carried a gun with him for safety reasons, so he was aware, but I don't think he was scared."
The defense attorney asked her about an incident in April 2012, when a car followed them in their car. Pistorius jumped out with his gun and held it to the window of the other car, which then disappeared. She confirmed the incident and said she was not afraid at the time.
She also testified that Pistorius never kept the gun under the bed, as he said in the bail statement that he did the night he killed Steenkamp.