Canadians who get behind the wheel while under the influence of drugs will face tougher consequences and will no longer be able to refuse roadside drug tests when new laws kick-in next week.

As of July 2, police officers will be able to require drivers to submit to a roadside sobriety test. As well, they can take drivers they suspect of being on drugs to a hospital for either a blood, saliva or urine test.

"More and more often individuals are refusing to give those samples and so now finally we are changing the law in this country that you will be compelled or you will be charged and I think that's a reasonable response to the problem," Justice Minister Rob Nicholson said Friday.

Under current laws, police who stop drivers they suspect of being under the influence of drugs can ask for a fluid sample to determine whether the person is intoxicated.

However, Nicholson said, police are also required to inform the individual that they aren't obligated to comply with the request.

RCMP Sgt. Robert Martin said that marijuana impairs drivers because it hampers a user's ability to process information.

"It slows down your perceptions," Martin said. "It impairs your ability to judge time and distance and reaction times."

Drivers who are convicted of drug-impaired driving will face a minimum $1,000 fine for a first offence. A second conviction could result in a month in jail.

The Conservative government is also making it harder for drivers to challenge breathalyzer tests in court, Nicholson said.

Representatives from MADD said the new law is a victory for the organization, because impaired driving is the number one criminal cause of death in Canada.

"Those people have committed a criminal act by driving impaired, whether it's by drugs or alcohol and as far as I'm concerned they've lost their rights," said MADD Canada president Margaret Miller.

However, defence lawyers believe that it won't be long before cases stemming from the new law end up at the Supreme Court of Canada.