It was probably the most watched moment in a criminal trial in Canadian history. Justice Denny Thomas read his reasons for finding Travis Vader guilty of second degree murder as more than 100,000 people watched live on television across the country, in homes, law firms and newsrooms.

Thousands more looked online, including a University of Alberta law professor, on sabbatical in Germany. That single camera, focused on the judge, was such a small step in giving Canadians a better sense of what happens in their courtrooms.

Yet it has taken so long and comes with no indication — and certainly no guarantee — it will happen again soon. All of this made me reflect on the many years I've spent trying to convince judges and lawyers that we need to better show Canadians their courts in action.

But in that time, I've learned some basic, frustrating lessons.

The myth of open courts

A senior B.C. judge I respect greatly recently addressed a public forum on justice issues by saying, "These are your courts. You have a right to see how justice is done. With very few exceptions, our courts are open and I strongly recommend you to come to the courthouse and see for yourself."

There is no question it is impressive, most of the time, to see the criminal justice system in action. You can learn a lot.

But there's a problem: While almost everyone I know has strong opinions about what happens in court, they don't feel they have the time to visit a courthouse. If we truly believe it's important to "see justice being done" — and I agree it is — we need to realize inviting Canadians to watch in person isn't good enough.

Justice Denny Thomas cites Section 230 of the Criminal Code 0:59

The 'slightest possible harm' approach

In my experience, when the media does apply for camera access to courts, every element of the legal profession — prosecutors, defence lawyers, academics — presents a united opposition.

Most troubling is how they abandon one of the great mechanisms in legal reasoning: Weighing the benefit against the harm. I've watched as lawyers ignored the benefits, but went to great lengths to create a long list of theoretical harms.

Without evidence, they rely on all the old clichés: Lawyers might grandstand, witnesses might be intimidated, the complainants and accused will lose their privacy. There are ways to address these issues, but no matter — that slightest possibility of hypothetical harm is enough, in case after case, to convince judges to keep cameras out.

Think about this: If we used this same standard for public attendance in court, almost every major criminal trial would be closed.

Bret McCann speaks to media outside after the guilty verdict was delivered by Justice Thomas in Edmonton on Thursday. (CBC )

Ignoring the evidence

There actually is a body of Canadian evidence of how cameras affect lawyers and witnesses, people accused of wrongdoing and the victims. That is judicial inquiries and commissions.

I've not heard of a single case where the cameras had a negative effect on the proceedings. In fact, in the highly contentious APEC hearings in Vancouver, where a senior RCMP officer and an aide to the prime minister were accused of serious breaches, I conducted long interviews with six key lawyers after the sometimes heated proceedings.

They represented the "accused," the complainants and even the commission itself. Every one said the cameras had no impact on them nor, as far as they could tell, on anyone else. They all said, after a few minutes, they forgot the cameras were even there.

And yet, in my experience, the lawyers opposed to cameras never consider what's happened in these inquiries and commissions.

Travis Vader faces first-degree murder charges in the deaths of Lyle and Marie McCann. Six years after the couple was last seen, Judge Denny Thomas will declare a verdict on the morning of Sept. 15. 2:13

I've made these points repeatedly to senior judges and, over the years, there's been a change. Now, they often agree with these points.

They also concede there's a troubling lack of public confidence in the court system and feel, as I do, the more people see the process, the more they understand and respect it.

But those discussions end in an invitation to make applications to individual judges to bring in cameras, and each hearing reverts to all the old approaches.

'Legal profession is willing to set logic aside'

By now, you know the twist in the Vader judgement. That Canadian professor in Germany, Peter Sankoff, watched online as Justice Thomas cited Section 230 of the Criminal Code.

Sankoff knew that section had been declared unconstitutional 26 years ago. Someone else would have eventually discovered the error, but he noticed the moment it happened and took to Twitter.

I see no possibility of saving the murder conviction. Judge based decision exclusively on 230. —@petersankoff

2/ Section 230 is unconstitutional, and you cannot convict someone of second degree murder using a definition of crime that's void. —@petersankoff

3/ Section 230 of the Criminal Code has been unconstitutional for 25 years. —@petersankoff

It gave us enough notice in our newsroom that we were able to have a thoughtful, insightful discussion with a legal expert that evening on CBC News Network. You could say this all happened in a timely way because the proceeding was broadcast live. You could celebrate that tens of thousands of Canadians, in a 300-channel universe, chose to watch a Canadian criminal proceeding live.

Honestly though, I worry that people will seize this opportunity to keep cameras out next time. No one is suggesting the live broadcast played any role in the judge's error.

But if I've learned anything in dealing with this issue over the last 20 years, when it comes to cameras in the courtroom, this is one area where the legal profession is willing to set logic aside.