Lambie said the government plan assumed it was easy to identify mis- and disinformation but experts said it was not.
“There are lots of problems with this bill and the government is rushing it. They only allowed seven working days to make submissions to the inquiry,” she said.
Rennick, who left the Liberal National Party in August and now sits as an independent, said Queensland voters were telling him they did not want a government agency to have power over claims made in public debate.
“The idea of having the government control over their version of the truth is extremely alarming,” he said.
Payman said she was aware of the concerns and would meet the Australian Christian Lobby next week to learn why religious groups opposed the draft law. She would decide her vote after more consultation.
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Victorian senator David Van, who quit the Liberals to sit on the crossbench, said he was open to passing the bill because it was mainly about the power to direct platforms to take down harmful content.
“If I’m right and that’s the full extent of the powers, I’ve got no problem with that whatsoever,” he said.
Communications Minister Michelle Rowland put the misinformation bill to parliament in September after a year of dispute over draft changes that drew objections from the Law Council of Australia and civil liberties groups about the threat to free speech.
The bill includes exemptions for the media and ensures that satire, parody and religious content will be protected.
To settle fears that ACMA would decide what was true or false, the government drafted the bill to leave those decisions to the social media platforms themselves, as long as they could show they had acted on complaints from the community.
Rowland insisted last month that the law posed no threat to free speech and was backed by security agencies that warned that false information was causing real damage in the community.
“Over 80 per cent of Australians are concerned about the rise of mis- and disinformation,” she said.
“The fact that it harms democracies, it harms economies, and the fact that action is needed in this area [means that] doing nothing is not an option.
“There are online harms that harm people socially. There are harms that harm economically, including in the area of scams. And there are also harms that go to our democracy.”
Coalition communications spokesman David Coleman has strongly opposed the bill on the grounds that those who wanted to silence opponents would claim a statement was misinformation and try to have it removed.
“A classic example is the Voice debate last year where the government, pretty much every day, said opinions they didn’t like were misinformation,” Coleman said last month.
“If this law had been in place, then I’m sure it would have been used and it would have had a chilling effect on that debate.”
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The Law Council expressed serious concerns about the changes last year. The NSW Council for Civil Liberties said it supported new regulation to hold digital platforms accountable, but wanted amendments to improve public transparency. The Victorian Bar, the peak group of barristers in that state, said the bill should not be passed.
“While the Bar acknowledges the importance of responding to false and otherwise harmful information online, such responses ought to only make justifiable incursions into socially valuable freedom of expression,” the Victorian Bar said in a submission to the government.
“The present bill is not justifiable in this respect and will have a chilling effect. It is also likely to be ineffective and unworkable in responding to the harms to which it is purportedly directed.”
Labor has 25 senators and is hoping to gain support from the 11 Greens but needs 39 votes to pass a bill in the upper house, forcing it to find at least three independents.
The government has at least 20 bills it wants passed by the Senate as soon as possible but has only scheduled two more weeks of parliament for the year, starting from November 18.
Prime Minister Anthony Albanese said on Friday the parliament would return in February, although MPs and senators privately observed that this would depend on whether Labor chose to go to an election early in the new year.
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