The former boss of Victoria’s anti-corruption commission has blasted the Allan government for acting as though it has unfettered power after it dismissed an auditor-general’s report that found another $12 billion in cost blowouts on major projects and criticised the government’s transparency.

Auditor-general Andrew Greaves’ annual assessment of major infrastructure projects, tabled in parliament on Wednesday, said an 8.7 per cent increase in spending in the past year had pushed the total estimated investment for state government projects to $145.5 billion.