If Ontario PC leader Patrick Brown forms government but fails to keep all five of his key campaign promises, he guarantees he won't seek a second term — even if the other parties are to blame.

Brown made the comments in my year-end interview with him, looking ahead to the 2018 provincial election campaign.

Since a PC minority government is one possible election outcome, I asked Brown if there are any exceptions to his pledge not to run again if he doesn't implement the central planks of the party platform called the "People's Guarantee." He said no.

"I'm just tired of having politicians make promises with no intention of putting anything behind those promises," Brown said. "I wanted more than mere words in a platform. I wanted to back it up with a guarantee that I'm all in, and if I don't get it done for the people of Ontario, then I wouldn't seek a second term."

I pressed Brown, "Even if you're a premier in a minority government, and the opposition gets together and blocks you from one of your key five promises, you will not run again?"

"If it's a minority parliament, I would work with other parties to make sure that we pass these five aspects," he replied. "I'm committed to this guarantee."

Ontario PC leader Patrick Brown (CBC)

Brown is also sticking with calling Premier Kathleen Wynne's Liberal government "politically corrupt," despite the acquittal of two senior party officials, including one of Wynne's closest advisers, in the Sudbury byelection bribery trial.

During their 14 years in power, the Liberals "may not have broken criminal laws but they certainly have broken the lines of what I think most Ontario families would view as appropriate ethical conduct," Brown said.

He said there is "no comparison" between police investigations into the Liberal government and the police investigation into the PC party's controversial nomination race in the riding of Hamilton West-Ancaster-Dundas.

"I instructed our team to provide any correspondence, anything the investigation was interested in, whereas you've got the Liberal Party was alleged to have deleted evidence," Brown said.

He was referring to the case of two senior aides to former premier Dalton McGuinty, who are on trial on charges of mischief and unauthorized use of a computer for allegedly deleting government documents about the gas plant cancellations. A ruling is scheduled for Jan. 19.

"This is almost two billion dollars the taxpayers are going to pay because of decisions the Liberal government took and then tried to cover up," Brown said. "We're talking about taxpayers being out billions of dollars, compared to overheated nominations where everyone and their brother seems to want to run for the PCs right now. I don't think that's a fair comparison."

Patrick Brown isn't saying what he will do if charges are laid as a result of a Hamilton police investigation into a contested Ontario PC nomination battle. (Claudine Brulé/Radio-Canada)

Hamilton police are investigating allegations by would-be PC candidate Vikram Singh that party officials rigged the nomination meeting to prevent him from winning. The Ontario PC Party has battled in court to keep a taped conversation about those allegations from becoming public.

During the interview, Brown declined to commit to a course of action if charges are laid against any party officials.

"I'm not going to get into hypotheticals," Brown said.

"Frankly, I think people are missing the bigger picture here," he added. "We've never had as many people wanting to run for our nominations. It's a sign of excitement that we have these giant nominations everywhere in the province."

The PCs are not committing to reverse several of the Wynne government's key initiatives that they have strongly criticized. Those include reforms to employment law, the privatization of Hydro One, and the 17 per cent reduction in electricity bills the Liberals call the Fair Hydro Plan.

"I'm not going to do anything that will cause the taxpayers to pay more. To unravel the unfair hydro plan would be too costly now," said Brown. "I wish they hadn't done it, it's going to cost Ontario ratepayers more, but they did it."

He rejects the NDP's pledge to bring Hydro One back into public hands as a "pie-in-the-sky" idea.

"Those shares are sold, the damage is done," Brown said. "You can't force a private shareholder to sell back a share to the province of Ontario."