Toronto Police can use sound cannons during the G20 summit with restrictions, a judge ruled Friday.
The decision by Ontario Superior Court Justice David Brown means officers can use the voice function of Long-Range Acoustical Devices, but not the ear-piercing alert function.
Toronto Police Chief Bill Blair said police will abide by the ruling. Officials said the force would formally change its procedures to comply with existing Ontario Provincial Police protocol by Friday afternoon.
"We are committed that it's … safe for the people of Toronto, safe for all the people engaged in protests and safe for our officers," he told reporters.
Chief Blair said police consider the devices communications tools. Toronto Police obtained four in the lead up to the summit.
The Canadian Civil Liberties Association filed an application for an injunction with the Ontario Superior Court earlier this month in an effort to disarm the controversial machines, which critics fear can cause lasting ear damage.
"We think it was useful for us to go to court, to seek the injunction and to force the police to be accountable for the way in which they are using new technology," said Nathalie Desrosiers, the group's general counsel. "They just purchased this, it has not been properly tested and it puts the health of the public at risk."
The devices have distinct communications and alarm functions. The former works as a high-tech speaker that blasts loud, prerecorded human-voice messages urging crowds to disperse. The latter is the ear-splitting siren that has given rise to many YouTube videos from past summits showing anti-globalization protesters fleeing police.
Manufacturers say loud sound is a perfect alternative to other force, but whether this amounts to sonic weaponry or a souped-up public address system is a matter of fierce debate.
Vancouver Police shut the door on the alert function when they acquired LRADs before the Olympics. Facing a civil-liberties outcry, Chief Constable Jim Chu promised it would be switched off. The RCMP does not use LRADs as crowd-control tools and limits their use to marine operations.
The devices were pioneered after al-Qaeda bombed USS Cole in Yemen in 2000 to help the U.S. military warn small crafts away from navy vessels.
With a report from Anna Mehler Paperny
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