The Vancouver Police Department says it likely filmed hundreds of thousands of people during the Celebration of Light, and the force is standing by its use of mass surveillance for the fireworks event.
Pairs of officers armed with video equipment could be seen at the event, and outside at least one transit hub hours before the fireworks began.
The Celebration of Light is typically viewed as family-friendly – Saturday's show drew between 300,000 and 400,000 people, yet Vancouver police reported only 11 arrests. Transit police reported nine.
The city is three years removed from the Stanley Cup riot, and Vancouver police spokesman Constable Brian Montague said the video cameras serve as a "subtle reminder" that police are watching.
"It lets people who may be intent on coming down to cause problems know that they're not anonymous in the large crowd," Constable Montague said in an interview Tuesday.
Robert Gordon, a criminology professor at Simon Fraser University, said the cameras essentially function as mobile CCTV units. He said he can understand why the police would want to utilize such a measure, though he believes it to be intrusive.
He said the cameras appear to be a legacy of the riot.
"It's a sad story, how a handful of idiots indirectly erode the civil liberties of everybody," he said in an interview.
The police spokesman would not disclose how many officers or cameras were involved, just that "multiple" recording devices were used. He also would not say how long the tactic had been in effect.
A Globe reporter spotted one pair of officers outside Granville Station, with their video camera aimed squarely at the exit.
Constable Montague said the 2011 riot after the Vancouver Canucks lost the Stanley Cup final showed that many of the people who attend major downtown events do so via transit.
When asked whether the video cameras were necessary for an event such as the Celebration of Light, he said the fireworks show wasn't quite so family-friendly about a decade ago.
"I can tell you that the Celebration of Light, internally here amongst the officers, was referred to as the festival of fights. We had robberies, we had stabbings, we had fights that were almost unbelievable to watch involving dozens of people at times. It was far from what I would call a family-friendly event. I personally would have never brought my family down to it," he said.
"We changed a lot of our tactics and one of those tactics that we changed was a large visible presence by police."
Video – whether it was shot by police, media, a member of the public, or captured via private surveillance camera – played a pivotal role in the Stanley Cup riot investigation. Video footage was played in court in many of the cases. More than 250 people have pleaded guilty.
After the riot, Vancouver police invested in new hardware and software that made it easier and faster to sort through large amounts of video.
The crowd for Saturday's Celebration of Light finale was one of the largest ever. In addition to the 11 arrests, Vancouver police reported 346 liquor pour-outs, 57 liquor seizures, six weapons seizures, and 46 violation tickets. Fourteen bylaw tickets were also issued.
On July 26, the first night of the event, Vancouver police reported a crowd of 250,000 people and 18 arrests.
On the second night, the department estimated the crowd at between 250,000 and 300,000 people, and reported 11 arrests.
Transit police reported three arrests on the first night of fireworks, and none on the second night.