The Canadian Civil Liberties Association is seeking a court injunction to prevent Toronto and provincial police from using the so-called sonic cannons until they have been approved as weapons by the government or the controversial “beam” function has been disabled.

The application, filed Monday, describes the long range acoustic device as “a non-lethal weapon that can be set to induce pain,” and argues that the instrument must be approved for use by the provincial solicitor general as other weapons are.

Toronto police, who have purchased four LRADs for the upcoming G20 summit, have skirted the regulatory process by referring to the device as a communication tool, said Nathalie Des Rosiers, general counsel of CCLA.

“It’s not appropriate to forgo a regulatory process by interpreting it very narrowly. The regulation in question does deal with tear gas. In our view, there isn’t much different between the sonic cannon and tear gas: They are both used to dispel crowds, they both can be used to coerce behaviour of demonstrators,” she said.

“The only thing we’re asking for is the proper process be followed.”

If the device isn’t approved, Des Rosiers urged the police to disable the alert function — an ear-blasting noise that surpasses the threshold of pain — from being able to be used in a steady beam of noise.

“If they decided not to use it as a weapon, then they could disable the alert function as the Vancouver police did during the Olympics,” Des Rosiers said. “It would go a long way to reassure people that the most strident noises and the beam aspect of it will not be used.”

Toronto Const. Wendy Drummond, a spokesperson with the summit’s Integrated Security Unit, reiterated the police service’s position that the LRAD’s will only be used for communication purposes.

“It is not classified as a weapon and it’s not intended to be used as a weapon. It’s going to be used as a communication tool. Our members will not only adhere to the manufacturer’s recommendation but also the guidelines imposed by (Toronto Police),” she said.

The machines double as loudspeakers and can blast booming messages in 50 languages.

Drummond said the machines will only be operated by trained supervisors or higher-ranking officers. In the case the alert function is used, it will be in two to five second bursts, as suggested by Toronto police and the manufacturer’s guidelines.

“The alert function is simply that: To alert the public, the crowd . . . to the fact that there is an upcoming message we want them to hear,” Drummond said.