Investigators with the Ontario ombudsman's office are once again looking into the actions of city councillors and the mayor, CTV News has learned.

And again it involves a conversation alleged to have taken place over a meal.

Councillors were notified early Thursday afternoon by the city clerk that an investigation is underway regarding the selection of Russ Monteith as the new Ward 5 councillor.

The office of the ombudsman states: "We will be investigating complaints that members of council met, allegedly in violation of the open meeting provisions of the Municipal Act on the evening of June 24."

Mayor Joni Baechler is not fazed by the investigation.

“We go through the process, cooperate fully and wait for the conclusion,” she says.

On June 24, 12 members of council had dinner in the Top of the Hall Cafe after selecting Baechler as the new mayor.

The next day there was a special meeting to choose a member of the public to replace her as councillor. It was a decision that could shift the balance of power on London's deeply divided council.

If council discussed and advanced its decision about whom to choose, it would violate the Municipal Act.

At that special meeting, councillors put forward four names for consideration, but after the first round of voting Monteith easily won.

“I don't recall any conversation at the dinner table in that regard whatsoever. I can't speak for the other tables but certainly there was none at my table,” Baechler says.

Coun. Harold Usher believes there was no violation.

“If this happened, it probably happened innocently - a name was thrown around. We were trying to figure out how are we going to backfill and people were throwing around names, but it doesn’t become official until it goes to the council,” he says.

“It sounds trivial to me, but I guess the ombudsman will have to decide that.”

Coun. Stephen Orser suggests many council dinners at the cafe involve conversations about council matters, but wouldn't say if he felt things crossed the line.

“I’ve said it for many years: What happens at the top of city hall is people communicate with each other. There were 12 members of council speaking and I will save my evidence for the ombudsman.”

In 2012, ombudsman Andre Marin investigated a luncheon at the Harmony Grand Buffet. No violation was found.

In 2013, he also investigated a lunch at Billy T's Tap and Grill and found that in that case, some councillor members met illegally.

Marin does not have the power to mete out any punishment, though.