It’s very telling that, when the ACF and Union Climate Connectors came to Canberra last week, a number of the grassroots campaigners they brought with them were shocked to discover that they were being asked to campaign for the CPRS, not against it. They thought they had been brought to Canberra to campaign for real climate action, not for the Rudd Government’s pretence of action.

A handful of environmentalists, nevertheless, along with a not inconsiderable number of Labor Party supporters, still argue that the CPRS is a step in the right direction. I often wonder what these people will think when, if the bill passes this week, there is a flurry of new investment in coal infrastructure in WA, Queensland, Victoria and NSW.

The government frames climate change as a blunt choice between action and inaction, but even they acknowledge as they negotiate with the Opposition that there is a point when action becomes so weak that it is useless. The Greens, of course, believe that point has been passed long ago and that the CPRS is beyond useless — it is worse than useless.

If the CPRS were merely weak, the Greens might have been in a position to support it. But we recognise that, when faced with a serious and complex problem, it is the choice of the right action that is vital, not the decision to act. Prescribing and locking in the wrong treatment to a seriously ill patient can hasten death rather than prevent it.

The Greens oppose the CPRS as it stands not because it is too weak but because it will actually point Australia in the wrong direction with little prospect of turning it around in the timeframe within which emissions must peak. This is why we say it is not just a failure, but it locks in failure.

There has been plenty of discussion around the fact that the 4-24% cuts (on 1990 levels) in the CPRS are actually undermining meaningful global action. There can be no global deal while rich countries like Australia refuse to play our fair role. But, while this is critical, it is not the most shocking way in which the CPRS takes Australia backwards.

The CPRS will unleash billions of dollars in investment if and when it passes. The Government wants you to believe that that investment will be delivering emissions reductions now and into the future, and a well-designed emissions trading scheme, with a science-based emissions trajectory and undiluted price signal, would indeed do that. But the CPRS will unleash short-sighted and ill-advised investment that will be very hard to turn around once the government is forced to do what it takes.

The Western Australian Government is talking about recommissioning two old coal-fired power stations that had been decommissioned. The Victorian Government is talking about refurbishing its existing brown coal plants. The Queensland and NSW Governments are planning new coal plants.

Not only will the CPRS not stop that investment, but it will actively encourage it. With its weak targets and price signal and the structure of the compensation – cash payments dependent on ongoing or increased generation – the CPRS could deliver coal a bonanza.

How can that be a step in the right direction?

What’s more, according to legal advice I released yesterday, if the CPRS passes and these multi-billion dollar investments are made, any future government would be liable to pay compensation to investors if they change the law to lift the targets and put polluters out of business.

This puts paid to the always flimsy argument from the Climate Institute and others that we should pass this bill now, regardless of how weak it is, and improve it down the track. That approach was always dishonest – equivalent to Peter Garrett’s “short, jocular conversation” prior to the last election when he said everything would change after Rudd was elected.

But it is also clearly out of step with reality. Peter Garrett was wrong in 2007, and his friends are wrong now. Nothing has changed because neither the government nor opposition want change.

If it is too hard to pass a scheme that works now, what on Earth makes anyone think it will get easier later? Once the political heat is off, it will get harder, not easier to drive real change. If we allow Rudd to get away with his spin-over-substance approach to climate change now, it will be that much harder to get a meaningful, science-based approach in the little time we have remaining.

This would be a horrendously expensive mistake to make, and it will be the community, not the polluters, who pay.