The company "does not consider that the broadcast of the segment has breached any relevant law, regulation or code," Austereo said, adding it would cooperate with any investigation.
On Monday, Austereo CEO Rhys Holleran said 2DayFM had tried five times, without success, to contact the London hospital to discuss the prank before it aired. The King Edward VII Hospital denied its management had been contacted by 2DayFM.
Media law expert Mark Pearson said that even if the station had tried to contact the hospital, that isn't enough under the law. He said permission must be granted by the person involved.
If the case went to court, it is possible that a judge could decide that an attempt at getting permission was sufficient, but only if the lawyers could prove that any "reasonable person" would agree that enough was done, said Pearson, a journalism professor at Bond University in Queensland state. He considered such a ruling to be a longshot.
"I think lawyers would be hard-pressed to argue that a few unprovable phone calls was enough to show that there had been a reasonable attempt to get permission," he said.
The case also could be investigated by the Australian Communications and Media Authority, the country's media watchdog. McDonald, the University of Sydney professor, said that stations found in violation generally are given warnings or told to train staff in proper procedures.
The authority has said it has received complaints about the hoax call and is looking into the case, but has not yet launched an official investigation.
Greig and Christian's comments Monday about higher-ups making the decision to air the call only raised more questions for Wendy Harmer, who hosted a morning show at 2DayFM from 1993 until resigning in late 2003.
Harmer said that when she was a DJ, she played an integral role in those decisions, and personally approved the many on-air pranks that she was responsible for.
The program producer, program manager and station manager needed to approve segments as well, Harmer said. She added that some segments were brought even higher to the group station manager for approval.
"If you're a DJ, and you're in front of the microphone, this is a very powerful medium and you should be absolutely apprised of all your responsibilities and all the rights of the audience," Harmer said. "And so to hear a couple of DJs who didn't seem to understand what those were was, I must say, alarming."
She added the company's statements that it had sought permission five times, and that the hoax call underwent legal review, are signals that the company knew "there's something big going down."
"I would say, 'If we have to bring the lawyers in, I'm not going to do it.' But I can say that with hindsight," she said.