Convicted murderer David Lyttle continues to deny he killed his friend Brett Hall almost a decade ago.
A jury last year found Lyttle guilty and he was sentenced to a minimum non-parole period of 11 years.
Hall's body has never been found after he went missing from his Whanganui property in 2011.
An undercover police operation in 2014 was set up and Lyttle confessed to the killing.
When arrested, Lyttle first told officers they had got the right man, but later claimed he was innocent.
During the 10-week trial the court was played many hours of recordings from the police undercover operation, saw a range of physical evidence and heard from dozens of witnesses.
Lyttle has returned - this time to the Court of Appeal - to appeal his murder conviction.
His legal team argued yesterday that the confession was unreliable.
Today Crown lawyer Mark Lillico told the court the confession proved Lyttle was responsible.
"'If you've listened to what I've told you it's self defence' (quoting Lyttle) - which is an implicit recognition that he is responsible for the homicide of Mr Hall," he said.
He went into specific details about the undercover operation, including the purchase of guns for a hunting trip.
Lillico told the court Lyttle had no gun licence.
Later, he read from a transcript in which Lyttle had mentioned where the body and weapons might be.
"'The guns are where I can't find them' .... "So you can't find them?' ... 'Oh is this where we went the other day... that's if nobody else has already found them because they cut all the trees down," Lyttle said to the undercover agent.
Lyttle's lawyer Christopher Stevenson said in reply that was not foolproof evidence because the story was changing.
The two-day hearing wrapped up this afternoon and the court reserved its decision.
Justice French thanked Hall's family at the back of the court and said the decision won't be released until next year.