Many opponents of the Tuggeranong power station and data centre base their objections on the contention that due process has not been followed.

The Greens and Liberals successfully campaigned for the auditor-general to inquire into how sites were assessed and whether appropriate consideration was made for environmental, social, health and safety risks. The inquiry is also examining whether agencies complied with relevant policies and best practices, including consultation.

In August, then Greens MLA Deb Foskey said the auditor-general's independent assessment would determine whether the proposal accorded with sound policies and proper procedures. The relevance of that inquiry is fast fading.

A key part of the planning process, an environmental impact statement, was still under way when the Greens and Liberals threatened to pass retrospective laws to prevent the project from being built on the preferred site. The threat was enough for the project's backers, Technical Real Estate, to ask the Government to look for alternative sites.

The draft environmental statement, issued yesterday, says the project meets all the desired environmental outcomes. Amid the debate and drama, the original aim of establishing a gas-fired power station to back up Canberra's electricity supply during periods of high demand has almost been forgotten. So, too, have the other benefits: making the ACT a leader in data-centre infrastructure, and replacing ageing buildings and outdated computer systems.

A more enduring legacy for Canberra is the uncertainty that now threatens this project and others of similar significance.

ACT Chamber of Commerce chief executive Chris Peters says the business community is alarmed at the extent of political meddling in planning.

That a project which meets all environmental tests can still be scuttled, irrespective of its compliance, will unsettle investors.

The ACT Property Council and Canberra Business Council say the debate demonstrates the need for the Government to consult a highly educated and environmentally aware community much earlier in future.

This is a delicate task while proponents canvass potential investors and try to protect their intellectual property.

What is crucial is certainty for investors in the ACT.

Property Council executive director Catherine Carter says when opportunities become uncertain, developers will look elsewhere.

The Opposition's view, that the project will not proceed under any circumstances, adds another unhelpful political dimension to the planning process.