An armoured vehicle is driving the Winnipeg Police Service to a crossroads that may lead to U.S.-style law enforcement, says Winnipeg criminologist Kevin Walby.

Police announced Wednesday that they've bought a Gurkha tactical unit. Walby's biggest concern is not that the service is getting the vehicle, but how that vehicle will be used.

"Do we want no-knock search warrants where police show up with this thing on your front lawn, 12 people with basically machine guns jump out, they kick in your door, and if you're holding something in your hand when they come through the door you could be shot? That's what's happening in the U.S.," Walby said.

"We're quite a ways behind but we're … at that fork in the road."

Walby has "several concerns" about the city's decision to buy an armoured vehicle: how it affects trust in police, effectiveness in future use and budget and accountability issues.

Several communities in Winnipeg are over-policed, Walby said.

"I think trust is an issue, so much so that we see community justice initiatives popping up where we see people say, 'We don't need police patrolling our streets. We can patrol our own streets [and] keep ourselves safe,'" he said.

"When we start rolling out these kind of armoured personnel carriers, they kind of look like tanks.… You can stick your gun out of it. Does it send the right message?"

Calling the vehicle "intimidating," Walby said he disagrees with Winnipeg police Supt. Gord Perrier, who said the armoured personnel vehicle is not a military vehicle.

"We've chosen a purpose vehicle that's built by a civilian manufacturer to be used in police operations and not military conversion," Perrier said Wednesday while explaining the decision to get the vehicle.

But Walby said the manufacturer's website reveals a list of clients from conflict zones around the world.

"[The manufacturer] sells it to different types of public and private entities in Libya, in Afghanistan, in four or five other conflict zones throughout Africa," he said.

"I don't think we can say it's just simply a civilian type of piece of equipment."