Local councils could be discussing matters of public safety and other issues that people have every right to hear, but some go out of their way to close the doors, added Marin.
"Some councils are still breaking the law, whether through ignorance or intent," he said. "My main concerns haven't changed: there are no consequences for breaking it."
The Bruce County council near Lake Huron held eight years of secret meetings with a government agency to discuss burying nuclear waste in the Kincardine area.
"I can't think of a case where there would be a greater case to meet publicly," said Marin.
The town council in Elliott Lake kept no records on 12 years of secret meetings, so officials could not find out if there were debates about the parking garage on the roof of the local shopping mall, which collapsed in 2012, killing two women.
"The commissioner (who headed the inquiry into the mall collapse) couldn't determine whether the risks of the mall were discussed during those meetings, and this is a situation of life and death," added Marin.
The independent government watchdog also singled out the Waterloo council for devising a "novel" way around the open meeting rule by having only small groups hold meetings but not enough for a quorum of council.
"I've rarely seen something so contemptuous of the rule of law," said Marin. "It was really an incredible disclosure by the city of Waterloo that they thought they could get away with it."
Municipal councils can have the ombudsman investigate complaints about closed meetings for free, or hire a "review officer" through the Association of Municipalities of Ontario, but Marin said they do shoddy work and err on the side of secrecy.
"Most of them write reports anonymously, which is kind of ironic when you're dealing with transparency at the local level," he said. "We found those reports largely to be riddled with inconsistencies, poor analysis of the facts and the law ... so poor the public interest is not being served."
A total of 196 of Ontario's 444 municipalities have agreed to use Marin to investigate complaints from the public about closed meetings, while 134 hired investigators through AMO's Local Authority Services.
AMO executive director Pat Vanini said local politicians need to get their direction from legislation and from government regulations, not from the ombudsman.
Marin also noted that the city of Brampton hired an investigator that bases fees on the number of complaints, so council decided anyone from the public that wants to complain about a closed meeting must pay $250 first.
"Guess how many complaints Brampton has had about closed meetings since 2008? Zero," said Marin. "There's no doubt that was set up to have a chilling effect, and it succeeded."
Until there are actual consequences for municipal councils that meet behind closed doors, Marin said he has few options to get them to play by the rules.
"Right now it's limited to public shaming, and that seems to work pretty good," he said. "One hundred per cent of our recommendations to municipalities have been adopted."
City councillors in Sudbury and London who fought against holding all their meetings in public went down to defeat in last fall's municipal elections, added Marin.
"They had a meeting with the electorate in October and the electorate made them walk the plank" he said. "It's only once every four years, but it's proven to be quite effective."'
Marin did not suggest what consequences offending politicians should face, but his report pointed out violating similar laws in Arizona, Georgia, Iowa, and Wisconsin can result in fines, and even in potential jail terms in Illinois and Michigan.
The ombudsman said he would soon be able to deal with a lot more local government issues because of the passage of the Public Sector Accountability Act in December, which gives him full oversight of municipalities, school boards and universities.
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