Bad information, once loose, persists. A false report is remembered long after a correction. But the ongoing debate about gun control in Canada is tainted by bad information. Let’s see what we can do about that.

Last year was a violent one in Toronto. Shootings were sharply up. A new record for homicides was set, with 96. In July, a particularly horrific attack in the Danforth neighbourhood left two people dead and 13 more injured. Toronto mayor John Tory, a generally sensible fellow who once (rightly) dismissed handgun bans as a symbolic gesture, reversed himself and called for one. Tory claimed that his position had changed because the facts had changed — more handguns being used in Toronto crimes, he said, were being procured by licensed Canadian owners.

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And it seemed like the mayor was onto something. The Canadian Press, shortly after the Danforth shooting, published an article quoting a Toronto police detective at length. The article specifically claimed that guns that could be traced back to Canada were now the leading source for criminals in the city, eclipsing the traditional source: smugglers bringing guns in from the United States.

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The number of “crime guns” — which in Toronto can mean not only guns used in crime, but also those illegally altered, or seized during criminal investigations — traced back to Canadian owners was “surging,” the article reads. “[Some Canadians] go get their licence for the purpose of becoming a firearms trafficker,” Det. Rob Di Danieli told the Canadian Press.

The Canadian Press provides news articles to most major news organizations across the country, Global News included. The piece was widely reprinted and was also cited in other reporting. It directly supported a renewed call for a handgun ban in Canada, a call that was taken up by city councils in Toronto and Montreal and is now being studied by the federal Liberals, who have campaigned on a handgun ban before — it was a key plank in Paul Martin’s failed 2006 campaign. It formed a central part of the debate that those calls provoked.

Its main claim — the surge in domestic guns used in crimes beginning around 2012 — was entirely based on the CP’s interview with Det. di Danieli. There appeared to be no independent verification. Dennis R. Young, a researcher and writer based in Alberta, filed a Freedom of Information request with the Toronto police, seeking precise figures dating back many years. The police obliged, and Young published the data verbatim online.

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Below: Data shows the number of ‘crime guns’ seized by Toronto police based that can be traced back to Canada and the U.S.

The details are in my column from September, and the data — the Toronto police’s own stats — showed no “surge” in guns traced back to Canadians. None. There was some ebb-and-flow across different years, but nothing like an emerging pattern, let alone a surge. The overwhelming majority of Toronto crime guns are never traced back to any particular source. Of those that can be traced either to the United States and Canada, the U.S. leads in most years, Canada in two, with one tie. There is nothing like a surge to be seen among domestic guns.

BELOW: Data comparing the number of crime guns seized by Toronto police that can be traced back to the U.S. or to lawful Canadian gun owners.

In September, I had obviously requested comment from Det. di Danieli and the CP. The police acknowledged my request to speak to the detective, and then never got back to me and ignored all follow ups. An editor at the CP told me that they were aware of and looking into the matter, and then ignored my follow ups.

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This pissed me off. Not in a sense of personal affront. I’ve been ignored before. But this incident is, to my mind, a black mark for both the Toronto police and the CP. Policing and reporting are both supposed to be about the truth. The police and the CP had combined to put out inaccurate information, and that inaccurate information was driving public debate. At minimum, a correction, or some comparable acknowledgement, was absolutely required.

None came. Until a few days ago.

On Dec. 27, in that quiet lull between Christmas and New Year’s, the Canadian Press published a new article. It wasn’t a retraction or a correction to their previous report. Indeed, the new article didn’t even refer directly to the CP’s earlier reporting. The new CP article, written by the excellent reporter Michelle McQuigge, detailed a year-end press conference by Toronto Police Service Chief Mark Saunders.

And this article, finally, sets the record straight. There indeed has been no surge in crime guns traced back to legally-licensed Canadian owners. “[Firearms] imported from the U.S. were implicated in … crimes more often than domestically sourced firearms in eight of the past 11 years,” writes McQuigge. “Domestically sourced crime guns only surpassed U.S. imports in 2010 and 2015, with the two figures tied in 2016.”

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As for the police, they have also, ahem, expanded upon their earlier statements. They told the CP that the majority of rifles and shotguns seized as crime guns by Toronto police are linked back to Canadians (which doesn’t surprise me). But they also finally admitted what should have been said months ago. Again, quoting a Toronto police spokesperson from McQuigge’s piece: “The majority of crime guns that are handguns seized by the Toronto Police Service are sourced via the U.S.”

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Well then.

Canadians have spent four months having a debate, including public consultations, based in part on bad information. Information that was known to be bad months ago, but that went uncorrected until two days after Christmas, when news readership is typically way, way below usual levels.

I’m not suggesting for an instant that there is not a problem with domestically sourced guns in Canada. The police definition of a crime gun is problematic — it includes guns seized during investigations that may not ever have been used in a crime, and also includes objects such as air guns that aren’t firearms under the law. So you have to take some of the stats with a grain of salt. But still. We should always have an open mind about ways to make our gun control system more effective at reducing crime.

But there is simply no evidence that there is a worsening problem among lawful Canadian handgun owners, the people targeted by the proposed ban — in effect, held up as partially responsible for tragic deaths and senseless crimes. The Toronto police numbers don’t show it. Nationally, the Public Safety Ministry has conceded that it has no data to support claims by Minister Ralph Goodale that domestic owners now provide the majority of crime guns. That entire narrative, embraced wholeheartedly by the mayor and somewhat more cautiously by federal Liberals, is based on bad information that should not have been reported.

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To call all this disappointing would be an understatement. In an era when news organizations all over the world are being accused of peddling fake news, and when every police force recognizes the challenge of retaining public trust, this is absolutely appalling.

I’m a reasonable guy. Stuff happens. Errors are made. The public is owed honesty, not perfection. Mistakes, when made, should be publicly corrected, as quickly as possible. Four months is too long.

Canadians got their honesty, eventually. Better late than never, I suppose. But damage has been done. My satisfaction in the truth finally being acknowledged — and there is some — is soured by that grim reality. Bad information lasts forever.

All we can do now, as properly informed citizens, is hold politicians accountable when they repeat that bad information, whether they’re doing so in ignorance or with malice. I’ll do my part. The rest is up to you.