LAS VEGAS (AP) " The lawyer for a former mixed martial arts fighter accused of trying to kill his porn star ex-girlfriend provided a glimpse Thursday of a key element in his defense: steroid use made him prone to violent outbursts.
Under cross-examination by defense attorney Jay Leiderman, former adult actress Christy Mack testified in Las Vegas that she saw Jonathan Paul Koppenhaver inject steroids and take pills during their 15-month relationship.
She said Koppenhaver, who legally changed his name to War Machine during his 19-fight MMA career, had bouts of depression and irritability. Koppenhaver has used his birth name since his arrest in September 2014.
Some studies link high doses of anabolic steroids with increases in users' irritability and aggression, according to the National Institute on Drug Abuse.
Mack acknowledged that Koppenhaver sometimes woke up in such a bad mood he went on what Leiderman called "Twitter tirades" about killing others and wanting to kill himself.
Koppenhaver has pleaded not guilty to attempted murder, kidnapping, battery, sexual assault and coercion that could get him life in prison without parole in incidents before and during an August 2014 attack on Mack and a man she was dating, Corey Thomas.
The Associated Press usually does not identify people who say they are victims of sexual assault, but Mack gave permission to use her name.
Mack, whose legal name is Christine Macinday, was guarded in some answers to the defense attorney's questions.
Was Koppenhaver prone to "sudden emotional outbursts?" Leiderman asked.
"I don't know if they were extremely sudden or if something (led) up to it," Mack replied.
Mack testified a day earlier that Koppenhaver beat her several times and raped her in the months before the August 2014 attack that injured her and Thomas. Earlier that year, she said she suffered a black eye, cut nose, a bite mark on her chin and a chipped tooth in an attack in a vehicle he was driving.
Thomas testified that Koppenhaver broke his nose and dislocated his shoulder before releasing him with a warning that if he went to the police, Koppenhaver would hurt him.
Mack said she escaped bleeding from her home, when she thought Koppenhaver was fetching a knife to kill her. She said he broke a knife during another attack that left her with shredded hair, cuts on her scalp, a broken nose, missing teeth, fractured eye socket, leg injuries and a lacerated liver.
Prosecutor Jacqueline Bluth asked Mack why she didn't defend herself.
"No way I could physically overpower him," Mack said, "and if I were to fight back, it would be 10 times worse."
Leiderman has not denied that the August 2014 fight took place. But he told the jury that Mack had rape fantasies and invited Koppenhaver to surprise her, and he cast the relationship as a mutual co-dependence that inevitably exploded into violence.
This story has been automatically published from the Associated Press wire which uses US spellings