As preparations continue for the sale of legal recreational marijuana Hamilton, Halton and Niagara’s top cops are raising a few red flags.

When it comes to impaired driving by drugs a Public Safety Canada survey found that 43% of Canadians don’t know how long to wait to drive after consuming pot. The fact is, the answer is still unclear.

Chief Eric Girt of Hamilton Police says, “The body of research for alcohol consumption goes back 40 or 50 years, we’ve established the physical indicators for the blood alcohol concentration. That research is not there.”

Drug impaired driving is not a new problem for police but based on other jurisdictions’ experiences after legalization, driving offences could go up.

“If it’s any indication what our colleagues in Colorado saw they certainly experienced a spike in impaired driving.” Chief Bryan MacCulloch, Niagara police.

The chiefs say that means they will need train more officers to detect impairment while they wait on a government approved saliva test.

In Ontario you will only be allowed to light up in your private residence. But some people may be bothered by the smell of pot smoke and neighbour complaints might increase.

The chief of Halton police, Steven Tanner says, “We have to clearly delineate with our municipal bylaw people on who will go to these types of calls and they will become neighbour disputes.”

Chief Girt is quick to point out another concern, “this is probably the largest country it has ever been done, geographically. We also have the poorest borders between us and the States.”

Raising the concern of American’s trying to smuggle drugs.

“There is a huge market that is illegal down south and there’s a huge profit margin should you do things illegally to traffic it and move it down there.”

But on this side of the border, Police Chief Tanner believes street gangs will continue to sell marijuana.

“Organized crime groups are going to sell stronger marijuana for less money and people are going to buy it.”

The Canadian Association of Chiefs of Police says it is unlikely it will reach its goal of having 2,000 officers trained to detect drug-impaired drivers when marijuana becomes legal. The Federal Government says it intends to approve a German made device that will test saliva samples before the legalization date of October 17th.