Gerard Baden-Clay had abrasions on his right cheek after his wife was found missing. He had them medically examined and he told the doctors that they were caused by shaving. The medical evidence allowed the jury to conclude that the abrasions on the husband's face were caused by fingernails in a physical confrontation with his wife. He also had a superficial scratch on the left side of his neck and marks on his chest. Bayden-Clay attributed these to having scratched itchy areas caused by a caterpillar landing on his neck.

The husband was having an extramarital affair which became known to his wife. He also had financial difficulties. There was transferred blood belonging to the wife on the surface of the back wheel arch of the wife's two month old car.

Beneath the bridge where her dead body lay, foliage from four different species of plants were found on Mrs Baden-Clay's clothes and in her hair from species found in the couple's backyard but not where her body was located.

But when someone is murdered without eye witnesses, the prosecution often has to prove its case by circumstantial evidence especially with regard to proving an intention to kill. There was plenty of circumstantial evidence in the Baden-Clay case.

At the trial, Bayden-Clay denied killing his wife. He did not give any excuse for why he might have accidentally killed her. The Appeal Court found that there was sufficient evidence for the jury to conclude that the husband killed his wife, contrary to his denial. The jury clearly rejected the evidence of the husband and his false denials. But the Court of Appeal found that there was insufficient evidence to find that the husband intended to kill his wife. In a baffling piece of legal reasoning it found that the evidence was consistent with the fact that the husband may have accidentally killed his wife even though he had denied in his evidence doing so.

The Appeal Court could and should have favoured an argument that having denied that he killed his wife, the jury in rejecting that explanation could rely upon his false evidence to conclude that he intended to kill his wife. If a killer wants to claim manslaughter for accidental death, adverse inferences should be drawn if the murderer does not give evidence of the fact and circumstances of any accident at the trial if they choose to give evidence. Murderers should not be able to first raise a technical defence of that kind at the time of an appeal through their lawyers and game the legal system by running a case which is inconsistent with the case at the first trial. The suggestion made by his lawyers on appeal that he may have accidently killed his wife was never able to be tested at the trial through cross examination.

The result of the Baden-Clay decision is to weigh the law in favour of the domestic violence killer and not his victim. The State of Queensland should appeal the decision to the High Court. If the High Court says the decision is correct or there is no appeal, then the NSW Parliament should, by statute, ensure that this result is never allowed to be followed in the Courts of our State. In NSW we want a judiciary that has laws which allow our Courts to arrive at decisions that reflect community values against domestic violence.

Alister Henskens, SC, is a barrister and the state member for Ku-ring-gai.