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The ACT's chief law officer has urged the High Court not to uphold an appeal against the constitutional validity of a gang rape leader's trial, warning such a decision would have "extensive consequences for the administration of justice" in the territory.
Success for convicted rapist Saimoni Vunilagi would render a long-standing regime of optional judge-alone trials unconstitutional, lawyers for ACT Attorney-General Shane Rattenbury have argued.
They say it would also cast doubt on the validity of some judicial appointments and the ability of non-court bodies, like the ACT Civil and Administrative Tribunal, to exercise certain powers.
Vunilagi, aged in his 30s, is currently serving a jail sentence of more than six years after former ACT chief justice Helen Murrell found him guilty of eight charges laid over a 2019 gang rape in Downer.
The Fijian, also known as Simon Vunilagi, was described as the "ringleader" of a group that met a young woman at Civic nightclub Mooseheads, then took her to a unit and sexually violated her.
Vunilagi, who denied wrongdoing, was forced to face a judge-alone trial in the ACT Supreme Court at a time when the territory had passed emergency laws to suspend jury trials as a result of the COVID-19 pandemic.
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He later unsuccessfully tried to convince the ACT Court of Appeal the decision to deprive him of a jury trial had been incompatible with the constitution.
That prompted a challenge in the High Court, which granted him special leave to appeal in June.
The court has since received written submissions from lawyers for Vunilagi and the ACT Director of Public Prosecutions, as well as counsel for the attorneys-general of the ACT, Northern Territory and Commonwealth.
In its submissions, Vunilagi's legal team, led by Bret Walker SC, raises two issues.
These include an argument that despite self-government, the ACT's laws derive their force from Commonwealth legislation.
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Vunilagi's lawyers argue he was therefore charged under "laws of the Commonwealth", which require trials to be conducted by jury.
In submissions filed on behalf of Mr Rattenbury, lawyers including ACT Solicitor-General Peter Garrisson SC argue Vunilagi's appeal should be dismissed.
They say the Court of Appeal was correct when it found the emergency laws did not engage the constitutional requirement for a jury trial where offences against "any law of the Commonwealth" were prosecuted on indictment.
According to them, the offences with which Vunilagi was charged and convicted are not defined in the relevant section of the constitution as crimes against "any law of the Commonwealth".
Mr Garrisson and his fellow barristers conclude their submissions with the warning that "success by [Vunilagi] would have extensive consequences for the administration of justice in the ACT".
If Vunilagi's arguments are found to be correct, the lawyers say, the "long-standing regime" of optional judge-alone trials for territory offences tried on indictment would be unconstitutional.
This would "overturn a long history of practice", dating back to 1993.
"Secondly, if the territory is not an independent polity, it is not apparent how ACT courts are not federal courts in which Commonwealth judicial power is vested by ... the constitution, with all the consequences that would entail," the Attorney-General's lawyers submit.
"This would impact, for example, the validity of appointments of acting judges and special magistrates, the schemes for inquiries into convictions, the permissibility of declarations of incompatibility under the Human Rights Act 2004 (ACT), and the exercise of judicial power by non-court bodies, such as the ACT Civil and Administrative Tribunal."
A date for Vunilagi's appeal hearing is yet to be set.