They had heard all the evidence in the case and, of anyone in the community "in the whole country", had the whole picture, Justice Graham Panckhurst told the seven women and five men who must now try to reach a verdict.
"You and you alone are best placed to evaluate the ultimate issues - was it David, and did he kill Robin as well; was it not suicide?" If ever there was a case where a broad spectrum of evidence required evaluation, "this is it", the judge said.
He spent almost five hours directing the jury and summarising the main points put by the Crown and defence during the three-month trial.
They had to decide if the Crown had proved beyond reasonable doubt David Bain killed all five members of his family - father Robin, mother Margaret, sisters Arawa and Laniet and younger brother Stephen - and had proved beyond reasonable doubt it was not a case of suicide in which Robin killed four of the family then committed suicide.
The judge urged the jurors to put aside anything they had heard before the trial, to "start with a clean slate" as they were asked to do when the case began on March 6.
An accused was entitled to be judged on the basis of the evidence, not on newspaper comment, rumour "or anything else".
The jurors had to put aside any prejudice or sympathy - there was "simply no place for emotion" in the difficult task of assessing the evidence and bringing in a verdict.
The previous verdicts from 1995 were gone - they had no status whatsoever, Justice Panckhurst said, telling the jurors they were "not here to re-examine the course of the first trial - it would be a mistake to do so".
References to what Joe Karam had done and what the police did not do were not their responsibility, but they were an important part of the history of the case.
When the Privy Council in 2007 found there had been a substantial miscarriage of justice and the matter should be heard again, it was careful to say its decision expressed no view whatsoever on the outcome of a new trial and that nothing in its judgement should influence the verdict in any way, the judge told the jurors, so their focus needed to be "grounded in the present". It could not be backward-looking.
In the course of their deliberations, they were entitled to reach deductions, to make inferences - logical, fair and reasonable conclusions based on the facts they found had been established by direct evidence - but they must not speculate or guess, the judge said.
The Crown case was entirely dependent on inferences, on circumstantial evidence, as no eyewitness had seen either Robin or David with a gun, Justice Panckhurst said.
And to consider circumstantial evidence the jury needed to look at each element advanced on an issue by issue basis and decide if the evidence "compelled" them to a particular conclusion. But the conclusion had to be logical, safe and "divorced from speculation".
There was quite a lot of hearsay evidence - something said by someone who had not given evidence in person but whose contribution was reported by others, the judge said. And they needed to consider with particular care hearsay evidence concerning what various people had said about Laniet's allegations of incest against her father.
Such evidence was that of Dean Cottle, a witness the judge said was "very reluctant" to come to court but whose previous statements were read to the jury. There were suggestions Mr Cottle had been blackmailing Laniet by threatening to disclose she was working as a prostitute and obtaining sexual favours from her.
There had also been a significant focus on evidence said to be missing. The defence said if samples of blood from Robin Bain's hands had been preserved for modern DNA analysis, the Crown case would be "turned on its head".
The jurors had to approach those matters in the same "balanced and fair way".
There was a large amount of expert evidence in the case and that was in a different category from the evidence of witnesses of fact. Various scientists, pathologists, fingerprint and ballistics experts, neurologists, urologists and other specialists had expressed their opinions.
Where there were diverging opinions, the jurors needed to consider the evidence carefully, and look at the limitations of any particular expert and whether they had strayed outside the narrow area of their expertise.
And one of the expert witnesses had made what the judge said was a sensible observation when he said it was "always best to keep things simple".
The question of a motive was something the jury was entitled to consider, although it was not essential because murder involved the intentional and deliberate killing of another. The Crown had to prove David Bain caused the deaths of his family and did so intentionally.
It did not have to prove motive. In this case, the defence said David Bain had no motive to kill but Robin did, because he was deeply depressed and about to be exposed for an incestuous relationship with Laniet.
But the jury was entitled to consider the question of motive and it could be "put into the scales". Character evidence in relation to David Bain could be relevant to his denials, the judge said.
But did the fact he was described by his friends as an entirely pleasant, gentlemanly, considerate and talented young man in 1994 show he was truthful?
Various witnesses had given evidence about seeing Bain on his paper round. It appeared he had run the round earlier on June 20. That evidence had to be taken into account when considering the time the family computer was turned on that morning.
Evidence relating to the calculations about the computer turn-on time was complicated and the jurors should use their collective wisdom when assessing the evidence. It might not be something where great precision was expected.
The question of the wound to Robin Bain's temple was a matter of contention. The defence said it was a contact or close contact wound consistent with suicide; the Crown argued it was not a wound consistent with Robin Bain having shot himself.
While the various expert witnesses found support for their differing views, it was a matter for the jury to sort out, the judge said.
Another area of conflict was the "gurgling" Bain said he heard from Laniet's room and what it meant in terms of the order of the three head wounds she sustained.
Crown and defence witnesses were at odds over whether the survivable wound to her cheek was inflicted first, then the two fatal shots to the top and side of the head, or whether they were in the reverse order.
And the defence also asked whether the sound Bain heard was from Laniet or whether it was caused by sound transference from the washing machine.
There was also evidence that bodies could make gurgling sounds after death, even if they were not moved by anyone.
The issue of Bain's fingerprints on the rifle was also a matter of contention, with strong disagreement about whether the prints were in blood or sweat. Also at issue was when samples for testing were taken from the weapon and where they were taken from in relation to the fingerprints.
On the matter of incest, the jurors had heard evidence from eight Crown witnesses and 10 for the defence.
The accounts varied, and the question for the jurors was whether what Laniet said was credible and reliable. also, was there a pattern where she seemed to have made the claims readily to people she did not know well but not to closer acquaintances or people who knew the family?
The jurors then had the various points argued by the Crown and the defence summarised for them before they retired for the night.
Judge's summing up
The jury must:
• Put emotions aside and assess the case dispassionately.
• Decide if the Crown has proved beyond reasonable doubt David Bain was the killer and that Robin Bain did not kill himself.
• Return a unanimous verdict on all counts.
• Make up their own minds on conflicting expert evidence and on hearsay evidence.
• Not re-examine the course of the first trial.
• Not make some sort of judgement based on Joe Karam's efforts since the first trial or what the police did not do.
• Approach speculation in a fair and balanced way.
Other points:
• The issue of who did it, Robin or David, must be proved by the evidence presented to them at this trial.
• David Bain started from a point of presumed innocence, because his previous convictions were gone.
• In all New Zealand, only the jury had the whole picture before it and was best placed to evaluate the ultimate issues.
• Proof of motive not essential because of the reality the motive might be buried and incapable of proof.
The Crown case:
• Laniet unreliable source of information.
• No medical evidence that Robin Bain was depressed.
• Bloodied footprints David's.
• Computer turned on just after David got home or very close to it - would someone hell-bent on committing suicide risk the 44-second wait for it to turn on, then type a message, then kill themselves?
• Robin Bain suicide does not fit.
• All items used in the commission of crime belonged to David.
• David heard the gurgling so must be the killer. Why did he wait 15 to 20 minutes before calling 111 if he heard gurgling that suggested she was still alive?
• Bloodstains on David's clothes linked him to fight with Stephen; there was none of Stephen's blood on Robin.
• Why would Robin Bain leave a lens and broken frames incriminating David, if he was the only one who deserved to stay?David's behaviour before the murders was unusual.
• David's fingerprints on gun in blood.
• Front room staged to look like suicide.
• Suicide note odd and a "get out of jail free" card for David.
• Paper run used as alibi.
• Washing machine not on.
• David changed his story.
• Why was Robin's body warmer than the others if he killed them and then killed himself within the same hour?
• David's injuries consistent with a recent fight.
The Defence case:
• Crown U-turned to shift focus to Stephen because its other evidence became too difficult to prove.
• Blood on David's shirt got there when stumbled around Stephen's room in shock.
• Untested bloodstains on Robin's hands could have come from his victims.
• Marks on his hands appeared to have come from teeth.
• Robin physically capable of fighting off Stephen.
• David had no motive, was happy.
• Robin was dangerously depressed and the allegations of incest made him flip.
• Bloodied footprints too small to be David's.
• Robin changed his clothes before killing himself because he was acting irrationally.
• Robin knew about guns.
• The computer was turned on before David got home.
• Robin committed suicide - forensic evidence proved his wound was a contact, or near contact wound, blood splatters were consistent with him shooting himself.
• David behaving as traumatised in the aftermath.
• Bloodstains on door frames consistent with someone shorter than David.
• He did not set out to be noticed on the paper run, would have been noticed anyway.
• Lens in Stephen's room had either been there for a long time or was planted there.
• David's injuries too insignificant to have happened in a big fight.
• If David was the killer, Stephen's body would have been colder because of how long he was on the floor in his underwear.
• Washing machine not going evidence a red herring.
• Nothing in the gurgling, bodies can gurgle and could have been something else making the noise.
• No blood under fingerprints on the rifle.
• Palm print in blood on washing machine explained by David putting the bloody jersey Robin left there in the wash.
• Sorry message not written in the syntax of a young person.
• No-one checked if there was any blood in the barrel of the rifle, as there was likely to be after Robin had killed himself.
