"This case has been popularly described as a whodunnit," said Justice Simon France as he summed up the Scott Guy murder trial.
The High Court judge told the jury of 11 in Wellington the case was solely about the allegation that Ewen Macdonald murdered his wife's brother.
"Your only task is to decide whether the prosecution has proved Mr Macdonald is guilty."
The judge said the standard of proof was "beyond reasonable doubt", which was a high standard to meet.
"It's not enough to say likely, or probable. At the end of the day, you must be sure."
The judge took the jury through the main thrust of the Crown and defence cases, the allegations and the counter claims.
He said evidence could be unreliable.
"We all have those moments. We thought we saw something, but we were mistaken. We're not lying, but we were unreliable.
"You, as the jury, have the benefit of seeing all the evidence; you need to sift though it. It's not a case of all or nothing. Some evidence can be accepted, other can be rejected."
The Crown case was a circumstantial one, but many criminal prosecutions did not have an eyewitness.
"There is nothing particularly unusual about a circumstantial case; it's not flawed or weaker for that reason."
The judge said the various strands by themselves may not prove guilt, but together they might. Not all strands were equal, and not every strand needed to be proven beyond reasonable doubt.
"That is for the ultimate question."
And each individual juror could take a different route to answer that question.
Sympathy and prejudice could play no part in the deliberations, said Justice France.
The wider Guy family was in a "horrible situation", and it was likely the jury admired the way Anna Macdonald, Kylee Guy and Bryan Guy, among others, gave evidence during the four-week trial.
"But your focus in the jury room should not be about providing closure for them, or giving them answers."
Similarly, the fact that Macdonald committed acts of criminal damage against Scott and Kylee Guy, and poached deer, did not mean the jury should leap to conclude that he committed murder.
"This trial is not about character."
Justice France said the Crown called the deer poaching evidence to show Macdonald was a skilled night-time hunter, not that he was a thief and able to escape detection.
Likewise, the arson and vandalism would be irrelevant in the trial had they been committed against anyone other than Scott and Kylee Guy.
The significance of lies was a matter for the jury, said Justice France. Macdonald had lied to police about damaging the two homes, admitting his guilt only when confronted with the statement of his accomplice, Callum Boe.
"People lie for many reasons, not just because they want to cover up an offence," said Justice France.
"These were offences against family, the whole family, so it's not surprising the family member responsible would not want to admit it."
Justice France discussed the evidence disputed between the Crown and the defence, including:
* Did Macdonald harbour a deep-seated grudge against Mr Guy, or were the rivals getting on better than ever?
* Could the murder be a burglary of chocolate labrador puppies gone wrong, as suggested by the defence. But why would a burglar shut the gates to force a confrontation?
* Was there two gunshots, or three? Was the 5am timing accurate?
* Was there a mystery sedan on the road?
The judge said all the evidence was interconnected, and all decisions on facts, and the weight given to facts, should be made together.
"There's a danger in considering things in isolation."
As he sent the jury members out to deliberate yesterday, the judge had some final words of advice, telling them not to be shy of reaching a verdict.
They will return to their deliberations at 9am today.