Warlpiri man Kumanjayi Walker died after Constable Zachary Rolfe shot him three times during an arrest attempt in Yuendumu, northwest of Alice Springs on November 9, 2019.
An inquest in Alice Springs into his death is exploring 54 issues related to his life and the actions of police before and after he was shot, including the quality of the department's coronal investigation.
NT police shared a full version of its coronial investigation report with the coroner but denied other parties access to some of it, including Const Rolfe's lawyers.
David Edwardson KC says if that continues coroner Elisabeth Armitage may have to disqualify herself because she has seen redacted information in the report.
He said that could impact her impartiality when discharging her duty, which includes considering if the police coronial investigation was fair.
"It could not be said the redacted portions, given the significance of the headings and the topics that are being discussed, do not bear very significantly on a clear issue Your Honour has to consider," " Mr Edwardson said on Friday.
"As long as the Proctor report remains in its redacted form and the defence do not have access to it and the coroners court has then the situation is untenable."
He said the NT Police Force had "a very considered and serious decision" to make.
"If, as they currently do, maintain the claim for legal professional privilege, and acting on the assumption that the mere provision of the unredacted report to the coroner does not amount to waiver, then the question of disqualification must necessarily arise."
Mr Edwardson said it was his opinion that the force had waived its right to confidentiality when it shared the full report with the coroner.
The hearing will continue on Monday with more submissions on the issue.
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