Is it a sonic gun that can cause permanent hearing damage and force large crowds to suddenly disperse?

Or is it a public address system that will allow police to more effectively converse with protesters during the 2010 Olympics?

The Vancouver Police Department is the first force in Canada to acquire a long-range, acoustic device -- what civil liberties advocates say is a powerful crowd control weapon capable of firing a concentrated beam of sound.

"Aside from what happened in Pittsburgh at the G-20 conference a month ago, it was only repressive regimes in the Third World that were making use of this," said Robert Holmes, president of the British Columbia Civil Liberties Association.

The long-range acoustic device, or LRAD, emits sound waves strong enough to cause intense pain, damaged hearing and temporarily disrupted vision. There has been no safety testing of the weapon in Canada, Holmes said.

Const. Lindsey Houghton, spokesman for the Vancouver police, confirmed Tuesday the LRAD was purchased for $17,000 over the summer and was successfully used by the department as a high-tech bull horn during the city's annual fireworks celebration.

Houghton insisted that while the device can emit piercing sounds, it will only be used as a public address speaker.

"The reason it was purchased is for the exceptionally good quality P.A. device that it serves us. We did not have the capability or any such device before it was purchased," Houghton said in an interview.

But later, Houghton said if police consider using the device for the pulsing sound, a number of conditions will have to be met.

"Any time we use something that is considered force, we have to meet the Criminal Code requirements for force. That force has to be reasonable, it has to be allowed under law," he said.

"If we're going to be using it for the function of moving away people in a riot-type situation, the riot proclamation has to be read. All that stuff has to be met before the feature is used."

When asked why the department would acquire a device that can emit piercing sounds if it only wanted public address capability, Houghton said those on the purchasing committee looked at a number of devices and decided the LRAD was the best option.

The device has been used by the U.S. military against insurgents in Iraq and by nations intercepting pirates off the coast in Somalia.

Holmes said he's concerned about the lack of guidelines around the use of the device.

"Where is the evidence that they have a firm knowledge of what it can do? Where are the studies about what it does to people it's used on? Where is the training? Where are the protocols?"

Holmes drew parallels between the introduction of the LRAD in B.C. and the introduction of the Taser.

He said even before the public inquiry examining Polish immigrant Robert Dziekanski's 2007 death at Vancouver International Airport has had a chance to report its findings, police are acquiring another high-tech device that can cause grievous pain.

"It's public money that is being spent on this thing and it's the public interest in ensuring that rights and freedoms are protected and that people are secure and safe and that our law enforcement community doesn't go out there with no standards," he said.

B.C. Solicitor General and Public Safety Minister Kash Heed declined to be interviewed, but issued a statement via email.

"From what I understand, this is a communications device that has already been used successfully by the VPD this summer at the Festival of Lights," Heed said.

"It was an operational decision by VPD to purchase it. They've been clear in how they intend to use it -- as an effective public address system."

Vancouver Mayor Gregor Robertson also turned down an interview request. But via email, Robertson said he's spoken with the police chief and has been assured the device will only be used as a public address system.

"However, I understand that people may have concerns, and I intend to clarify the department's policy around use of the device at the next police board meeting," he said in the statement.

David MacAlister, a criminology professor at Simon Fraser University, said the public should be concerned whenever the police get new powers or new devices that don't contain strict policy guidelines.

"It's yet another tool in the hands of the police and we're seeing ever-increasing tools, weapons . . . in the months leading up to the Olympics," MacAlister said.

Holmes recounted a recent conversation with a city councillor who said the civil liberties association was out of line for comparing protest restrictions leading up to the Games in B.C. to those in Beijing.

"Vancouver joins China in embracing these devices," Holmes said.

Houghton insisted there won't be any crackdown on protesters during the 2010 Games and said the force has been working with groups to ensure lawful protests can take place.

He added that the LRAD is nothing new since the force has long had access to noise-emitting devices that can subdue crowds.

"They're the sirens on our police cars," he said.