Australian state governments could sue tobacco companies for billions in public hospital and health costs under a proposal developed by a former lawyer who helped legally establish that passive smoking causes lung cancer. The South Australian government has formally sought advice on the proposal, while other states are considering it.

The proposal is by Neil Francey, a research fellow at Sydney Health Law. Under it, states could bring proceedings in the federal court seeking up to $50 billion in damages for health costs and to fund cancer screening programmes and prevention measures. The proposal targets the dominant tobacco companies in Australia – British American Tobacco (BAT), Philip Morris and Imperial Brands – and their overseas parent corporations.

Francey is presenting the draft at the annual scientific meeting of the Clinical Oncology Society of Australia in Sydney on Thursday. He argues that the companies could be liable for decades of misleading and deceptive conduct under Australian consumer protection law. Francey has also briefed representatives of state governments. Under the plan, six state governments would pool resources to establish a dedicated, joint legal working group to lead the case.

The proposal states that the tobacco industry has unjustly enriched itself for decades while distracting and confusing smokers about the harm and addictiveness of its product. The industry was not forced to bear the full costs of the damage caused by its product, and those costs were borne by smokers or taxpayers. A spokesperson for BAT Australia said the company does not comment on potential or impending legal claims, while Philip Morris and Imperial Brands did not respond to requests for comment.

Francey told the Guardian Australia that the proposal excludes the Northern Territory and the ACT because territories are part of the Commonwealth and there are differences in health funding arrangements that could complicate the case. The proposal seeks to recover health costs that states have incurred since 2000, when internal tobacco industry documents were released revealing that the industry knew smoking caused serious diseases but participated in concealing and obscuring the evidence. Francey said: "I think you can justify a figure of the order of fifty billion, maybe even more."

In 1991, Francey represented consumers in a case in the Australian federal court prompted by an advertisement by the Tobacco Institute of Australia which claimed that "nothing scientifically proves that cigarette smoke causes disease in non-smokers". The court found compelling scientific evidence that passive smoking causes lung diseases and respiratory problems in non-smokers, rendering the industry's claims unlawful. That judgment accelerated smoking bans in workplaces and public enclosed spaces.

Francey said his latest proposal has the advantage of being driven by state governments under consumer protection laws, bypassing some challenges faced by smokers in personal injury lawsuits, where it is difficult to prove which brand caused the harm, and tobacco companies argue that people have "freedom of choice". State governments could seek court orders against companies that engaged in misleading and deceptive conduct leading to loss and damage and the probability of future suffering.

South Australian Health Minister Blair Boyer said there is a "significant" public interest in measures that reduce the harm caused by tobacco-related diseases to governments, health systems and communities. "While this proposal relies on historical findings of misleading and deceptive conduct by the tobacco industry, it is important that the state conducts its own due diligence," Boyer said. "I have sought advice on the proposal, the likelihood of success and the benefits for South Australians, which will allow the government to consider its options."

A spokesperson for NSW Health Minister Ryan Park said: "We will carefully review his proposal." A spokesperson for Queensland Health Minister Tim Nicholls confirmed a meeting with Francey but said the state is focused on laws targeting illegal tobacco and vaping trade. Western Australian Health Minister Meredith Hammat said the state's efforts are currently focused on strengthening tobacco legislation and enforcement activities.

Australian Council on Smoking & Health executive director Laure Hunter said it would be "entirely reasonable for tobacco companies to bear the costs of the damage their products have caused" in Australia. "For years they have profited from selling products that make people addicted and cause serious illness and death," Hunter said. "Responsibility for addressing that damage lies with the companies that profited from it." Legal pressure follows cases abroad, including the landmark Master Settlement in 1998.