The number of Australians travelling overseas to fight for terrorist groups has drastically reduced since Peter Dutton was given the power to strip dual nationals of their citizenship, the Home Affairs department has said.
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But national security strategists say there is no real proof the laws are acting as a deterrent.
The department told the joint intelligence and security committee while the number of Australians attempting to travel to war zones in Syria and Iraq had "markedly diminished", about 80 who fought for or supported Islamic extremist groups remained overseas.
"There remains the potential for a number of these individuals to attempt to leave the conflict zone and seek to return to Australia," the department said.
"Ceasing the citizenship of people who have engaged in terrorist-related conduct helps ensure that membership of Australian society is limited to people who retain allegiance to Australia.
"The cohesion and strength of the Australian community is, ultimately, the best defence against violent extremism."
But the Australian Strategic Policy Institute's director of national security, Dr Isaac Kfir, and head of the Strategic Policing and Law Enforcement Program, Dr John Coyne, said they struggled to find any proof the citizenship laws had dissuaded anyone from joining the various Salafi-jihadi groups.
"This suggests that this policy isn't rooted in empirical assessments. If the government has such information, we urge it to share it with the public," they told the committee.
Dr Kfir and Dr Coyne also said the people interested in joining violent extremist groups were unlikely to be deterred by the threat of having their citizenship revoked.
In fact, the laws were making it some people less likely to cooperate with authorities.
"We are concerned that among certain minority communities, primarily the Muslim community, there is growing distrust of the authorities, a sense of structural discrimination and Islamophobia," they said.
"Local authorities, police and community activists have worked tirelessly to address concern that many within minority communities have, which has led to improved cooperation, which may have led individuals to feel confident to discuss certain issues and individuals of concern with the authorities."
But the strategists told the committee there was a fear that should someone lose their citizenship and get deported, individuals would be less likely to cooperate.
Separately, the Home Affairs department admitted provisions that enabled the citizenship of foreign fighters to be automatically stripped has put pressure on Australia's foreign relations.
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Under sections 33AA and 35 of the citizenship act, citizenship ceases automatically as soon as an individual engages in terrorism-related conduct.
"Citizenship cessation applies automatically and may thereby reduce the availability of other mechanisms, such as criminal justice processes, that can be used to manage the level of risk an individual poses to the Australian community," the department said.
"The ability of Australia to manage its broader bilateral relationships and equities can also be affected by the automatic operation of law."
Legal groups also continued their opposition to the laws, on the grounds of insufficient safeguards and lack of due process.
"A dual national's citizenship can be removed without proper notice or a reasonable opportunity for them to present their case and respond to any adverse findings prior to their citizenship being stripped (except where the minister determines their citizenship cases following criminal conviction)," the Human Rights Law Centre said.
The centre also said the standard of proof for determining whether someone was a dual citizen was also lacking.
"The case of Neil Prakesh whose citizenship was stripped under this scheme illustrates how the citizenship removal provisos can be used to strip Australian citizenship based on the false and unconfirmed presumption that a person is a national of another country," they said.
"Determinations of dual nationality are inherently complex and difficult as the crisis over parliamentary eligibility under section 44 of the constitution proved."
The Australian Law Council said the Prakesh case showed there was a high risk Australians could be left stateless by the laws.
"This is not consistent with Australia's international obligations and is an undesirable consequence of the existing legislation," the council said.
Up to 93 Australians have been killed fighting for overseas terrorists groups in Syria and Iraq, data to August 2018 - released under freedom of information - shows.
About 40 foreign fighters returned to Australia after fighting for overseas groups.
About 230 Australians were being investigated for supporting terrorist groups involved in the conflict, while about 240 passports have been cancelled or refused for foreign fighters.
