Top barrister and executive member of the Law Council of Australia, Fiona McLeod, SC, told Fairfax Media that while an improvement on previous proposals, the legislation introduced to Parliament this week was "far too broad".

Ms McLeod said that the laws would invest great power in public servants to decide whether the threshold had been met to strip a person's citizenship using information and intelligence that might never be made available to the suspect themselves.

"It can be on the basis of completely untested material which we know can be completely unreliable," Ms McLeod, who is also president of the Australian Bar Association, said.

"We know that intelligence about weapons of mass destruction led us to war in Iraq. We know that courts are suspicious of intelligence because … often it's obtained under duress or coerced or obtained from a source motivated by who-knows-what.

"But we're trusting the ability of a public servant to assess the credibility of that information without even a full intelligence assessment."

She said the range of reasons why a person can be stripped of their citizenship was "so broad that they catch far too much".

These included people who might have been involved with terrorist organisations unintentionally or under duress, or even people who had provided humanitarian services to members of those organisations.

"Doctors from Medecins Sans Frontieres might be said to be providing service to terrorist organisations for patching people up who walk in the door," Ms McLeod said. "Aid workers for the Red Cross or Red Crescent might be caught for simply being on the ground and handing out water and food.

"When they talk about fighting for or in the service of one of these organisations, they are casting the net so broadly that they might catch people who they cannot possibly intend to catch."

And regarding the process for a judicial review, the law excluded natural justice, appeal rights and ministerial duties in ways that "severely limit the ability to bring an effective administrative review of those decisions".

Immigration Minister Peter Dutton told Parliament this week when he introduced the bill that citizenship was "something to be treasured" but "regrettably some of the most pressing threats to the security of the nation" came from Australian citizens involved in terrorism.

"It is now appropriate to modernise provisions concerning loss of citizenship to respond to current terrorist threats. The world has changed so our laws should change accordingly," he said.