The religious discrimination bill differs from similar existing laws despite advocates of the bill claiming otherwise, Australian legal experts say.
Yet the attorney-general's department says it is still within the Commonwealth's constitutional powers to legislate.
On Friday, the federal parliamentary committee on human rights began its third hearing on a religious discrimination bill controversially introduced to parliament in the final sitting weeks of 2021.
Introducing the bill in November, Prime Minister Scott Morrison said it would fix a weakness in Australia's discrimination laws.
He compared the bill to existing sex, racial, disability, and age discrimination laws.
Representatives from the attorney-general's department tasked with drafting the bill told the committee it would work concurrently with other anti-discrimination laws.
However, acting deputy secretary Andrew Walter said the bill's statement of belief clause could override existing laws.
Law Council of Australia representative Katherine Eastman told the committee the council was concerned this aspect of the proposed bill did not meet international human rights obligations.
"The bill does more than simply build defences into existing discrimination laws, it preferences rights based on religion over and above the equality rights that sit under the suite of other discrimination laws," she said.
Freedom of Faith board member Neil Foster said the bill's inclusion of the contentious statement of belief clause was reasonable.
The clause states it will not be discriminatory for a person to say something they "genuinely consider to be in accordance with the doctrines, tenets, beliefs or teachings of that religion".
However it does not apply if the statement is malicious or threatening.
The department said the bill included this clause to allow flexibility.
"(Religion) is a different ground for protection and different to values for existing laws which go much more to the characteristics and attributes of an individual," acting deputy secretary Walter said.
Associate Professor Foster said any concern people would use the clause to infringe on the rights of others was unrealistic.
"We don't see religious groups at the moment engaging in this sort of bizarre, hateful speech," he said.
"It may be wrong, it may be terrible, it may be bad for religious people to say things based on their faith which upset other people, but it's not unlawful."
But the Australian Human Rights Commission said that meant the statement of belief clause was unnecessary because it does not address an issue that needs fixing.
AHRC President Rosalind Croucher said current discrimination law was not preventing people from making the kinds of statements the proposed bill would allow.
She said the commission supported a religious discrimination bill that was more similar to existing discrimination law, but the bill as proposed was not.
Meanwhile co-convenor of the national network for the LGBTIQ+ community Jason Masters said the statement of belief clause was the most concerning part of the bill.
"I'm very concerned when people say there's not the standard of evidence (for discrimination), because the standard of evidence has never been accepted in the past," he said.
"The LGBTQI+ community has never been listened to."