Outgoing High Court judge Bill Gummow ruled this week that the full court would hear the challenge to the constitutional validity of the Australian Crime Commission Act 2002, following a complaint from a person summonsed to give evidence under the commission's special coercive powers.
The plaintiff, called X7, was called to give evidence to investigators at the ACC about federally-related crimes with which they are charged and awaiting prosecution.
By law, the identity of the person, the reasons for the ACC summons and any information surrounding the interrogation cannot be published.
X7's lawyer, Gabriel Wendler, told Justice Gummow there was a question whether the Constitution provided protections to X7 that prevented interrogation by a policing body while charges for the same matter were before the courts.
"If one breaks up the process you have an executive inquiry which leads to a charge," Mr Wendler said.
"When that process is over the charge commences a judicial inquiry.
"Now, (during) that judicial inquiry there cannot be a parallel system, so to speak."
Central to his argument, was whether X7 had a constitutional right to not reveal their defence to the criminal charges.
"The construction question will turn on the issue whether there has been effectively an abrogation of a fundamental right, namely that the administration of justice not be interfered with," Mr Wendler said.
"The curial (court) process, once it is activated by the laying of a charge, must take its normal course."
Michael O'Meara, for the ACC, said he would argue that there was no risk X7's interrogation would interfere with the federal criminal charges.
By law, the ACC has similar powers to a royal commission, allowing examiners to summons a witness and require that they give the commission evidence of their knowledge of criminal activities in which themselves and others are involved.
