A Sydney man who fatally stabbed a close friend after they consumed a cocktail of drugs told police his companion made it clear "only one party was leaving the house alive", a jury has been told.
Henry Walcott, 30, has pleaded not guilty - on the grounds of self-defence - to murdering Cameron Bradley, 34, in November 2016 at an Airbnb in Leura in the Blue Mountains.
Prosecutor Guy Newton told the NSW Supreme Court on Monday that Walcott told police his friend made it clear he was more keen for Walcott to kill him than vice-versa.
Defence barrister Brendan Green said there'd be no dispute that in the lead-up to the death, both men ingested illicit drugs, that Mr Bradley died from a single stab wound and that his client inflicted the wound.
But it was up to the Crown to prove Walcott did not act in self-defence, he told the jury.
Twelve hours after Walcott rang triple zero to report the stabbing, he made statements to police in a hand-written document which police then video-recorded him reading out.
He referred to the men having some "really interesting and insightful" conversations before Mr Bradley changed "in the way he was making dialogue" around 3 to 4 am on November 10, the prosecutor said.
Walcott felt his friend was "suggesting I have a personality disorder of some kind" before Mr Bradley openly conceded he had a sociopathic personality and "was trying to convince me I had one too".
The prosecutor said Walcott referred to his friend making it clear that "only one party was leaving the house alive" and Mr Bradley was keen "on me killing him rather than the other way around".
Walcott said Mr Bradley had spoken of depression and suicide in the past. He told police his friend said "if I was not going to do it, he was going to very soon".
Walcott revealed he'd grabbed a knife from the kitchen but Mr Bradley became aggressive and they had a scuffle and struggled before "I noticed a clear path to the neck area so I took it", the prosector said.
Walcott rang triple zero at 12.07 pm telling the operator he had "killed someone" with a knife and that they both had consumed illicit drugs for a number of days.
He later told police the stabbing occurred at about 10 am and he had driven around before returning and making the emergency call.
"The Crown says the conduct of the accused after he stabbed Mr Bradley was not consistent with a person acting in self-defence," Mr Newton said.
The trial continues before Justice Robert Allan Hulme.