Australia’s competition regulator Rod Sims says Facebook has the capability to deal with the proliferation of fake news on the platform, but the social media behemoth is instead “palming off responsibility” to protect its bottom line.

In an interview with Guardian Australia, the ACCC chairman says the social media giant should have removed the bogus death tax claims in circulation during the federal election contest in May, given its own independent fact checking processes had found the material to be false.

Sims said he felt more comfortable talking about processes necessary for dealing with disinformation on digital platforms than “opining on particular situations”, but he said: “If you know the information is wrong it should be removed. If you know it’s false, it should be taken down.”

In sharp commentary about the practices of the social media giants, the ACCC chairman said digital platforms wanted to pursue a profitable business model where they were, in essence, publishers, but without exercising any editorial responsibility.

“It’s that mentality and desire to set up a platform, control the platform and control everything that’s done on it, and have no responsibility for anything that goes wrong – that’s Uber’s business model, but writ large that’s Facebook and Google’s model,” he said.

Guardian Australia has revealed as part of an investigation into the death tax misinformation that the Labor campaign pressed Facebook repeatedly to deal with the false claims shared on the platform during the federal election, and escalated their complaints in the final week.

Facebook is firmly in the sights of Australia’s competition and consumer regulator as a consequence of its review of digital platforms. Photograph: Dado Ruvić/Reuters

But the social media giant declined to play censor.

Simon Milner, the Singapore-based vice-president of the social media giant in the Asia-Pacific, told Labor after the election in correspondence seen by Guardian Australia: “We do not agree that is is our role to remove content that one side of a political debate considers to be false”.

Milner confirmed in the same correspondence that Facebook’s independent fact checking procedures had determined the death tax material was actually false, not just considered by Labor to be false. The Facebook executive said once the claims were found to be false on April 30, “we demoted the original posts and thousands of similar posts”. Posts were demoted in Facebook’s News Feed but not removed from the platform.

Responding to Milner’s arguments, Sims said Facebook – which has faced intense blowback in other jurisdictions – had been through a period where “they don’t want to have to admit [disinformation on the platform] is false, and then say we aren’t going to do anything about it.

“I think there was a time when they were in that mode, but they realise it’s a bit tricky now, so they are hiding behind “who are we to judge, who are we to arbitrate” to the point where Mr Zuckerberg is saying we want governments to arbitrate, and that is again palming off responsibility I think.

“They have to take responsibility, and the idea that they can’t; I understand they don’t want to, but I reject the fact that they can’t.

“They can. They have massive technology. They can do all this stuff. They just don’t want to do it because it would damage their bottom line.”

Facebook is firmly in the sights of Australia’s competition and consumer regulator as a consequence of its landmark review of digital platforms.

One of the recommendations of the ACCC review, released in late July, was digital platforms be required to implement a code of conduct to govern how they handled complaints about the spread of inaccurate information, which would be registered and enforced by an independent regulator such as the Australian Communications and Media Authority.

Sims said implementing that recommendation would change behaviour. “They can take responsibility by having a code about how they deal with disinformation, how they deal with copyright, having an ombudsman with the power to determine what should happen with a complaint.

“One of those three headings would deal with the [death tax case study] or if one judges that a narrow interpretation of our recommendations wouldn’t quite get you there in that situation because it’s more a political thing than a commerce thing, [the regulatory structure] could be easily adjusted to deal with that.”

Sims was clear that in order to force behavourial change, “the codes have got to be compulsory, they’ve got to be enforceable and there’s got to be penalties for breaching them.

“It shouldn’t be like the food and grocery code, which has no penalties for breaching it, and is a very bad governance model, that requires you to do something but there are no consequences if you don’t do it.

“That to me just erodes public faith in government.”

He said if the Morrison government’s response to the digital platforms review was to implement a process where the platforms were accountable to independent regulators, and that would be “a great step forward from where we are now”.

“It might not be the end game. Things can evolve if that doesn’t work as well as we’d hoped, if there are complex judgments that the regulator and the companies can’t make, then we may need to look again.”

In a recent interview with Guardian Australia, the communications minister Paul Fletcher said he has some sympathy with Facebook arguing it is not responsible for taking down lies circulating on its platform, because the social media giant does not hold itself out as a traditional media publisher with editorial standards.

Fletcher said he wasn’t inclined towards establishing “an Australian government office of truth verification, and this office would be charged with putting a tick or a cross against items on social media, and then, inevitably, against items on conventional media”.

“That is clearly not a workable solution and it creates more problems than it solves.” But the minister flagged changes to ensure the social media giant was required to help its users better assess the veracity of content.

In response to a question about whether the experience of the 2019 election and the election before, where Labor unleashed the “Mediscare” campaign against the Coalition, whether it was now time to consider requiring truth in political advertising, Sims said he didn’t want to “get ahead of ourselves”.

“It could be that the issues raised by Facebook and Google accelerate that issue and make it more urgent to do something – but that’s down the track.”