Prime Minister Stephen Harper unveiled new legislation on Friday that will target drivers who get behind the wheel while stoned on drugs.

"The legislation will among other things provide police with more tools to detect drug-impaired driving, increase penalties for drug-impaired driving, strengthen presumptions of breath and blood tests and promote awareness about drug-impaired driving with partners like (Mothers Against Drunk Driving)Canada," Harper said at a press conference.

"Our goal will be to replicate many of the successful efforts over the past few years that have educated about the dangers of drunk driving."

The legislation aims to make drug-impaired driving as socially unacceptable as drunk-driving has become, Harper said.

Though the legislation will move to "strengthen presumptions" of breath and blood tests, there is currently no appropriate test in Canada to test for drug impairment.

"There are technological challenges in terms of testing for certain kinds of drugs," Harper conceded.

"But there are certain tests available and there are ways to strengthen the legislation to get convictions in clear cases" of driving under the influence of drugs, he said.

The new legislation, which will be introduced when the House of Commons returns from its Remembrance Day break, is designed to help deal with the growing threat of drug-impaired driving, Harper said.

Harper made the announcement in Kitchener, Ont. while attending the MADD-sponsored 19th Annual Project Red Ribbon Campaign.

Senator Marjory LeBreton, whose daughter and grandson were killed more than a decade ago by a drunk driver, also attended the press conference.

"As a father, I can only begin to imagine how truly awful it must have been for Marjory to have heard that news and then to live with the pain of having lost her loved ones. But Marjory is not the sort to sit still and drown in her sorrows," Harper said.

"Instead, she set out to ensure that a similar tragedy does not befall other families. She joined with the courageous campaigners who are working to eradicate impaired driving across this country."

LeBreton called the announcement ''gratifying'' and a clear move towards making Canadian roads safer.

Andrew Murie, chief executive officer of Mothers Against Drunk Driving Canada, told CTV Newsnet that the legislation is a good start.

He said more and more frequently, drug use poses a real danger on the roads.

"We've realized that in some respects, especially with young people, they've switched their drug of choice. They've gone from drinking and driving to using cannabis and driving," Murie said.

While drugs, and particularly cannabis, erode a different set of skills among drivers than alcohol, they are still potentially lethal.

"The person who is impaired by cannabis is just as much a risk to other road users as somebody who is above the legal limit with alcohol."

Murie, who attended the announcement, was to have a brief private meeting with Harper later on Friday.

While police have been requesting this type of power for a long time, there has not yet been a scientific roadside way for them to determine which substances a driver has taken.

Murie said that a drug recognition evaluation system that is currently being used in the United States may be a solution.

Using a series of tests, a trained officer is usually capable of determining what drug a driver has been using. A bodily fluid is then demanded to confirm the results.

With the test results, the sample, and the officer's assessment, Murie said "it's been proven successful to get a conviction" in U.S. courts.

Murie wants Harper to go even further than the U.S., adding at least one to three new improvements to the current legislation.

First, Murie said speculation is that the Tories may remove the right of someone found with a blood-alcohol reading of more than .08 per cent (the legal limit for driving) to show evidence in court that they were not as intoxicated as shown on a breath analysis machine.

Currently, drivers can bring six friends to court to testify that they only had one or two beers on the night of the arrest.

As a result, judges throw such cases out 60 to 70 per cent of the time, said Murie.

Second, Murie said he hopes the legislation will give police the ability to demand testing of any driver involved in an accident.

Third, Murie wants to see the implementation of a private member's bill currently before the House that would make driving with a blood alcohol level between .05 and .08 a separate offence.

The bill was introduced by a B.C. Conservative and Harper could decide to make it a government-backed proposal, said Murie.

But the legislation drew criticism from Associate Liberal Justice Critic Brian Murphy.

Murphy said the new measures were "hypocritical" give the fact the Tories recently cut $4 million from the Royal Canadian Mounted Police's elimination of drug-impaired driving program's training budget.

"The Liberal Party obviously supports measures taken to prevent drug-driving," Murphy said in a written statement.

"But this prime minister needs to explain to Canadians why he made such significant cuts to the RCMP, scrapping a training program that helped officers detect drivers who are under the influence of narcotics."