Tobacco companies are not philanthropic institutions. As long ago as 1967 the late Senator Robert Kennedy said, "the cigarette industry is peddling a deadly weapon. It is dealing in people's lives for financial gain".

The Australian tobacco industry is dominated by three big companies (or in modern political parlance, three "great big" companies), British American Tobacco, Philip Morris and Imperial Tobacco - all overseas-owned, with decisions made not in Sydney or Melbourne but in London and New York.

These are tough and ruthless multinational corporations, promoting and selling a product that kills one in two of its regular users. They have known for sixty years that their product is lethal. During this time almost one million Australians have died because they smoked - while the tobacco companies have denied and downplayed the evidence, doing their utmost to oppose and delay any action that might be effective in reducing smoking. Around the world their products cause five million deaths a year - a figure which will only increase as their drive into developing countries bears lethal fruit.

The new Chief Executive of Imperial Tobacco, Alison Cooper, was recently reported in the UK media as still refusing to accept that smoking causes cancer. Small wonder that only last week a survey of the reputations of the UK's largest 150 companies had Imperial Tobacco at 147 and British American Tobacco at a rock bottom 150.

There is massive evidence from once-confidential industry documents now available following litigation in the US that for decades tobacco companies have acted more cynically than even tobacco campaigners might have thought - summarised by a quote from an industry executive - "We don't smoke this shit, we just sell it. We reserve the right to smoke for the young, the poor, the black and the stupid."

And as if all this were not enough, the industry has been found guilty of racketeering in the US.

Tobacco companies have only one aim, in London, New York or Canberra. In line with their responsibility to their shareholders, they spend money with the sole purpose of benefiting their interests.

So why would anybody want to take money from this pariah industry?

The Australian Electoral Commission website reports that in recent years both the Philip Morris company and British American Tobacco have been generous donors to the Liberal Party and the National Party. During the year 2008/9 Philip Morris contributed $158,000 to the Liberal and National parties around Australia.

No doubt in addition to direct contributions there is also much indirect funding from groups supporting and representing tobacco companies, but this is much harder to pin down.

The only reason for these contributions is to further the interests of tobacco companies. The website of the British American Tobacco company is quite explicit about political donations: "Such payments can only be made for the purpose of influencing the debate on issues affecting the company or Group..."

A review of tobacco industry political donations in the US, published in the American Journal of Preventive Medicine, concluded that, "tobacco industry monetary contributions are closely related to the way a legislator votes on tobacco issues", and "The more campaign contributions received by a Congress member, the more likely he/she votes pro-tobacco on tobacco-related bills".

Political donations are not simply about an intention to buy direct support: they are also about much less tangible benefits gained through indirect support, influence, contacts, access and credibility.

The Greens and Democrats took the lead in refusing tobacco industry funding, followed by the ALP. The other major parties understand the dangers of smoking; they know exactly why tobacco companies want to give them money; it is hard to imagine that they would knowingly take money from drug dealers - and yet they seem content to accept contributions from an industry whose products cause more than 80 per cent of Australia's drug deaths. Surely there is something awry with the moral radar of anyone who accepts this kind of blood money.

The argument we sometimes hear that this is a "legitimate industry" is old and tired. If cigarettes were a new product they would not be allowed on the market. Our parliaments have decreed that the product is so harmful that it should not be sold to children and adolescents, should not be advertised, and that its sales should be subject to ever-increasing controls. This is no ordinary product, no ordinary industry.

The Australian government now leads the world in action to reduce smoking, complementing strong action in most jurisdictions (other than the Northern Territory, whose lack of interest in tobacco remains a mystery).

It is time for all political parties to refuse tobacco funding, or for legislation that forbids such contributions from companies that still seek to oppose the work and recommendations of governments and health authorities, and whose products cause 15,000 Australian deaths each year when used precisely as intended. Then we can be assured that all parties are making policy on this vital public health issue free of the taint of association with tobacco companies, and free of any suspicion that their policies might be influenced by these disreputable, lethal donors.

Mike Daube is Professor of Health Policy at Curtin University.