The full bench of Australia's highest court has torn apart an appeal court ruling, saying part of the decision to downgrade Gerard Baden-Clay's murder conviction was based on "mere speculation or conjecture", not evidence.
The convicted wife killer's own evidence at trial was enough for a jury to reasonably reject his defence team's subsequent claims Allison Baden-Clay's killing could have been unintentional, five justices found unanimously.
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Baden-Clay decision is 'massive'
A decision by the High Court to overturn a finding by the Court of Appeal will "fundamentally alter" criminal law in the Commonwealth.
In a decision delivered on Wednesday, they rejected several of the Queensland Court of Appeal's key reasons for downgrading the former real estate agent's conviction to manslaughter.
Baden-Clay lied at trial, claiming he had nothing to do with his wife's death, whether accidental or intentional.
His own defence team "expressly rejected" the unintentional death hypothesis at trial, according to the High Court, in what the Crown's submissions labelled a "murder or nothing" defence.
Then when it came to an appeal, Baden-Clay's lawyers for the first time put forward the possibility their client had accidentally killed his wife.
The Court of Appeal accepted the argument, ruling the evidence didn't allow the jury to be satisfied beyond reasonable doubt of an intent to kill, and allowed the appeal.
The five justices said not only did Baden-Clay's evidence not raise the accidental killing hypothesis, it was capable of ruling it out.
![Kerry Anne Walker, a close friend of Allison Baden-Clay, reacts after High Court reinstated the murder conviction of ...](/web/20160901182813im_/http://www.brisbanetimes.com.au/content/dam/images/g/r/5/a/i/x/image.related.articleLeadwide.620x349.gr5kwd.png/1472627616034.jpg)
"The Court of Appeal's conclusion to the contrary was not based on evidence," they wrote.
"It was mere speculation or conjecture rather than acknowledgment of a hypothesis available on the evidence.
![Allison Baden-Clay.](/web/20160901182813im_/http://www.brisbanetimes.com.au/content/dam/images/z/z/l/w/1/image.related.articleLeadwide.620x349.gr5kwd.png/1472627616034.jpg)
"In this case, there was no evidence led at trial that suggested that the respondent killed his wife in a physical confrontation without intending to kill her.
"There were 'no positive proved facts from which the inference' drawn by the Court of Appeal could be made."
![Kholo Bridge, where the body of Ms Baden-Clay was found after it had been dumped by her husband.](/web/20160901182813im_/http://www.brisbanetimes.com.au/content/dam/images/z/v/2/8/y/image.related.articleLeadwide.620x349.gr5kwd.png/1472627616034.jpg)
The ruling found the jury had plainly not believed Baden-Clay's lies, but they could not be disregarded altogether.
They were important because it was open to the jury to consider that, as the only witness, his evidence had ruled out the very hypothesis his defence ended up arguing on appeal, that he'd fought with his wife and killed her accidentally, the High Court found.
![Baden-Clay went to lengths to attempt to disguise cuts on his face as coming from a razor.](/web/20160901182813im_/http://www.brisbanetimes.com.au/content/dam/images/g/i/t/v/z/d/image.related.articleLeadwide.620x349.gr5kwd.png/1472627616034.jpg)
"The hypothesis identified by the Court of Appeal was not open," it ruled.
"Once that hypothesis is rejected, no other hypothesis consistent with guilt of manslaughter, but innocence of murder, has ever been identified at trial, before the Court of Appeal or in this Court."
The justices went on to find fault with the Court of Appeal's assessment of Baden-Clay's motive for murdering his wife and dumping her in the creek.
He was in deep financial trouble and carrying on an affair he promised had ended, with his mistress and wife likely to meet at a real estate conference the next day if he had not killed her.
Even so, the appeal court found "there was no evidence of motive in the sense of a reason to kill".
It accepted the "evidence of financial stress and the extra-marital affair suggested a context of strain between the couple which might well have culminated in a confrontation" but concluded "it did not provide a motive or point to murder rather than manslaughter".
"That was an error," according to the High Court.
The justices found the lower court's decision did not account for Baden-Clay's promise to his mistress, Toni McHugh, that he would leave his wife by July 1. Nor did it address that he could not afford a divorce and that his wife and mistress could meet the following day.
"The respondent's false denials to police about his ongoing affair, his suggestion to Ms McHugh that she should "lie low", and his enquiry of her as to whether she had revealed the affair to the police were all capable of being regarded by the jury as evidencing a strong anxiety to conceal from police the existence and true nature of his affair with Ms McHugh," the High Court found.
"This anxiety could reasonably be seen as indicative that, in his mind, the affair and the killing were interrelated, and that the killing was not an unintended, tragic death of his wife, but an intentional killing."
A court of appeal should not substitute trial by appeal for trial by jury, the Court of Appeal noted.
After killing his wife, Baden-Clay went to lengths to attempt to disguise cuts on his face as coming from a razor, even including his daughter in the deception.
The Court of Appeal found this evidence was "neutral as to motive" but the High Court disagreed.
It ruled the jury was open to consider this conduct "beyond what was likely" for someone who had unintentionally killed his wife and criticised a "piecemeal" approach to the evidence.
"In all the circumstances of this case, other than speculating about how things might have happened, it was open to the jury rationally to conclude that the respondent killed his wife and did so with intent, at least, to cause her grievous bodily harm," the court ruled.
Baden-Clay's murder conviction and life sentence have been reinstated.