The High Court has narrowed the possible defences in an NT police officer’s upcoming murder trial. 

Northern Territory police officer Zachary Rolfe has been charged with murder over the death of Kumanjayi Walker in 2019. 

Mr Walker died after being shot by Constable Rolfe, who had gone to the community of Yuendumu to arrest him over a breach of a suspended sentence.

Constable Rolfe’s trial has been delayed to allow prosecutors to ask the High Court to throw out the “good faith” defence.

This came after the full bench of the Northern Territory Supreme Court ruled he should be able to use the defence.

The matters relate to section 148B(1) of the NT's Police Administration Act, which says a person may not be held civilly or criminally liable for something done in good faith in the exercise of their job.

Northern Territory prosecutor Philip Strickland told the High Court that the NT Supreme Court’s ruling may have prevented a jury from considering whether Constable Rolfe's actions were reasonable.

“If they found there was a reasonable possibility that the respondent fired the fatal shots in good faith to protect [his colleague's] life then that would be sufficient to grant an acquittal,” he said.

“They would not, therefore, need to consider the standards of reasonableness either at statute or common law.”

But the High Court this week unanimously allowed the appeal from prosecutors, meaning Constable Rolfe's “good faith” defence will be subject to other constraints.

The argument may still be used under common law or statutory powers, but it will be “subject to constraints, such as doing only that which is reasonable and necessary”.

“In granting special leave, the High Court also emphasised that while it was necessary to correct the Full Court's error, it should not be assumed that the High Court would do so in every case given the undesirability of fragmenting the ordinary course of criminal proceedings,” the High Court noted. 

Constable Rolfe may also rely on self-defence in the trial, as he faces a murder charge as well as back up charges of manslaughter and engaging in a violent act causing death.

More details are accessible here.