The man who pushed Andy Marshall to his death through a second-storey window in Cottesloe has said his first instinct afterward was to get home and out of harm's way.
Stefan Schmidt walked out of the Ocean Beach Hotel in May 2011, looked at Mr Marshall lying on the ground in a pool of blood, hailed a taxi and went home.
He has admitted to pushing Mr Marshall but denies he intended to kill or harm the 29-year-old.
Mr Schmidt told the Supreme Court yesterday he had pushed Mr Marshall because he looked like he was about to intervene in a discussion he had just started with two female acquaintances.
The former rugby player said after he saw Mr Marshall fall he was scared a "mob mentality" might develop at the beachside hotel.
"My first instinct was just to go home," Mr Schmidt said. "I was scared. I was in disbelief. I couldn't believe what had happened and I was worried everyone at the club was going to turn on me as well."
But under cross-examination, prosecutor Bruno Fiannaca accused Mr Schmidt of deliberately pushing Mr Marshall through the window to prove himself to a friend.
He said Mr Schmidt would not have been in a state of disbelief after Mr Marshall fell because he had achieved exactly what he set out to do in a fit of rage.
"You knew what you had done was wrong because there was no reason for you to violently push Mr Marshall," he said. "You intended to do him some serious harm."
Mr Schmidt, who weighed 152kg at the time, told the court he had taken two ecstasy tablets and smoked marijuana before he got to the pub, but said the drugs had little effect on him.
Mr Schmidt said he had always intended on handing himself in to police and he went home after Mr Marshall was killed so he could process what had just happened.
On his way home, he sent a text to a friend that told that person they would never be the alpha male again.
In June 2012, Mr Schmidt was sentenced to a minimum 14 years for murdering Mr Marshall but his conviction was overturned last year.
The retrial is in front of Justice John McKechnie alone.