Modern slavery laws need fines, Labor says

Businesses could be fined more than $1 million for failing to disclose what they're doing to stop modern slavery in their supply chains under changes proposed by Labor to draft laws.

Opposition justice spokeswoman Clare O'Neil says it's not good enough if big businesses "can't be bothered" to comply with reporting requirements, which ask companies with turnovers of at least $100 million to disclose their possible modern slavery risks.

"Modern slavery is everywhere we look, but we're not looking enough," Ms O'Neil told the lower house when debating the bill on Wednesday.

There are 48 million people trapped in modern slavery globally, including 4300 Australians.

Ms O'Neil said Australians could inadvertently support modern slavery by simply eating seafood, with reports of workers forced to work on Thai fishing vessels for years.

"We can't be sure if the seafood on these boats is making its way onto our dinner tables," she said.

"Their lives might feel remote, but in reality their lives and ours are intertwined."

Labor is seeking to introduce an independent anti-slavery commissioner and to remove forced marriage from reporting requirements, fearing companies would interfere in the private lives of employees.

"We're worried that the bill as currently drafted may inadvertently push forced marriage further underground," Ms O'Neil told AAP in a statement.

The Morrison government has vowed to lead by example, by considering possible modern slavery risks in procurement processes and publishing a regular statement.

Liberal MP Chris Crewther says the complex and extensive issue exists even in his outer-Melbourne electorate, with a woman found hidden in the wall cavity of a brothel in 2013.

He said companies with a turnover of less than $100 million could opt-in to report on possible links to modern slavery in their supply chains.

"I urge colleagues to take a bipartisan approach to this issue that should not exist in modern society," he told parliament.