The commitment that made Ben Carroll premier may ultimately cost him the election.

On Monday morning, right in the middle of a state election campaign, the royal commission into Victoria’s Big Build will begin two weeks of public hearings.

For Labor, this is the worst possible timing. It wants to be talking about anything other than allegations of corruption and criminal infiltration of government projects . For the Coalition, it is a gift they will exploit.

Carroll – whose campaign bus is splashed with the words “new premier, new direction” – will face sustained questions about the actions of his predecessors and a past he wants to move away from.

Labor insiders fear the next two weeks could be damaging.

“If there are bad news stories, Ben will be up in the media and we will not change our plan,” says a senior Labor source.

“He’ll say ‘I set this up, I want answers’. Ben is owning it.…