"I've seen the reality of what these crimes are like at the coal face and it's not something you can turn away from," Ms David told AAP.
The leading index was co-founded by mining magnate Andrew "Twiggy" Forrest to eradicate modern slavery from the world's mines, factories, food supply chains, brothels and construction sites.
A global slavery index was co-founded by mining magnate Andrew "Twiggy" Forrest. (Lukas Coch/AAP PHOTOS)
Some 50 million people are being exploited, with more than half the global total working in slave-like conditions in the Asia-Pacific region, according to the International Labour Organisation.
Given the scale of local resources, the Future Made in Australia (Production Tax Credits and Other Measures) Bill 2024 could counteract these hidden human costs and reduce the reliance on minerals from countries with human rights concerns, Ms David said.
Under the $22.7 billion manufacturing package yet to pass parliament, generous credits would go to Australia's future critical mineral refineries, hydrogen producers and green aluminium smelters for a decade to get them over the line commercially.
The opposition, leading in opinion polls with a federal election due within months, has dismissed it as "billions in handouts to billionaires".
As the world's largest producer of rare earth elements, China routinely sources much of its raw supply from Myanmar with "under-the-table deals" allegedly made with local militias for illegal mines and child labour, Ms David told a senate inquiry in a submission by Fair Futures.
Reports of workers deceptively recruited from China to work in Indonesian nickel smelters include allegations of dangerous conditions, violence, lower wages and longer work hours than agreed, passports confiscated and arbitrary deduction of wages, she said.
Australian nickel producers have shut down as Indonesia floods the market with cheaply produced nickel, a vital metal for batteries and other clean energy equipment.
China also has a monopoly on lithium supplies, with processing operations in Xinjiang in Western China under scrutiny over forced labour concerns involving Uighur and other Muslim nationals, Ms David said.
As with lithium, a growing amount of cobalt processing occurs in Xinjiang, which has strong links to forced Uighur labour, she said.
An allegedly exploited Uighur workforce is supplying poly-silicon, a vital material in solar panels. (Aaron Bunch/AAP PHOTOS)
A Uighur workforce is also being used to supply poly-silicon, a vital material in the production of solar panels, according to NSW Anti-slavery Commissioner James Cockayne.
Australia's Modern Slavery Act was passed in 2018 to "send a clear message that modern slavery is unacceptable in the supply chains of all of our goods and services", the coalition government said at the time.
"One solution is building alternative supply chains, and critical minerals is an absolute no-brainer," Ms David said.
The Senate Economics Legislation Committee inquiry is due to report back on the tax credits bill by January 30.
