Senior Canadian police officials told MPs studying the government's marijuana legalization legislation that police won't be ready to enforce new laws by next summer, and they are now asking the government for more time.

The government has vowed to legalize the drug by July 1, 2018, and introduced a bill in the House of Commons last spring to do just that.

"If legislation is ready to go July 2018, policing will not be ready to go Aug. 1. It's impossible," said Rick Barnum, deputy commissioner of the Ontario Provincial Police.

"I think we are very close. I agree that something had to change. This is a great step …, but we've got to do it right and do it slowly and properly," said Barnum.

OPP deputy commissioner Rick Barnum tells MPs on Tuesday that police will not be ready to enforce new legislation by next summer. (CBC)

"We are asking that the government consider giving us more time to have all the legislation fully in place which will allow us to properly train, prepare for implementation on Day 1," said Mike Serr, co-chair of the Canadian Association of Chiefs of Police drug advisory committee.

This request was braced by testimony from Kevin Sabet, president of the U.S.-based organization Smart Approaches to Marijuana, who had a clear message for the committee: "slow down."

"The only people that benefit from speed in this issue are the business people that are really waiting to get rich. There is no benefit to going fast on this issue at all," said Sabet. "I understand it may be too late, but I still think that forgoing legalization in favour of reducing criminal sanctions and deterring marijuana use is the best way from public health."

MPs also heard from Thomas Carrique, co-chair of the Canadian Association of Chiefs of Police organized crime committee. Carrique said a lack of adequate police training can lead to poor decisions and bad case law that will impact the sustainability of the law before the courts.

'Mitigate' but not 'eliminate' organized crime

MPs were told the new legislation will not eliminate organized crime in the cannabis industry, echoing comments made Monday by a senior RCMP officer.

"This legislation will not eliminate organized crime, but there is an opportunity to mitigate the impact organized crime has on our communities," said Carrique.

Carrique said the opportunity to mitigate will be found in improved regulations and more stringent security screenings that include not just cannabis companies or licence holders, but also the investors, contractors and suppliers.

"If you follow the money, you will find the organized crime. It is currently a $7 billion illicit industry in this country. There are over 300 criminal organizations that are currently involved in the production, distribution, importation or exportation of cannabis," said Carrique.

Colorado, Washington experience

Officials from both Colorado and Washington — two states that legalized recreational marijuana in 2012 — also appeared before the committee today. Both states have robust security screening processes around the production and retail of recreational and medical cannabis.

"Any business that wishes to enter this space and or any employee that wished to work inside of the space has to come through my department," said Michael Hartman, executive director of the Colorado Department of Revenue.

Hartman said individuals and businesses must pass an FBI background and criminal check and their finances are scrutinized to ensure no criminal element is involved. An official from Washington indicated that state has a similar security screening regime.

Michael Hartman, executive director of the Colorado Department of Revenue, tells MPs about the state's experience with legalizing recreational marijuana. Tuesday, Sept. 12, 2017. (CBC)

The committee also heard the legalized regime appears to be competing well with the illicit market in Colorado. Hartman said a 2014 demand study showed that 70 per cent of the market demand was being supplied by the regulated marketplace. Hartman said Colorado is in the process of updating that study and anticipates a significant increase in that market share.

Rick Garza, director of the Washington State Liquor and Cannabis Board, said Washington believes that once the price of legal cannabis fell to about $10 per gram they were able to compete effectively with the illicit market. Garza said the price of cannabis in the state is now down to about $7.48 per gram.

The committee is holding five full days of uninterrupted hearings.

Along with the witnesses, the health committee has also received 106 written submissions.