Prime Minister Stephen Harper received enthusiastic applause from the nation's police on Monday as he reiterated his government's promise to toughen the federal justice system.

Just hours before the opening of the new Parliament, the prime minister took time out to be the keynote speaker at a conference of the Canadian Professional Police Association at Ottawa's Chateau Laurier hotel.

Harper reiterated campaign promises to impose mandatory minimum prison sentences for drug crimes, weapons offences and crimes committed while on parole. He also spoke of his government's plan to end conditional sentences for serious crimes such as weapons offences.

Prime Minister Stephen Harper says he will find a way to put more police on the street.

"If you do a serious crime, you're going to do serious time," he said to applause.

"It's quite remarkable the prime minister has found the time for us," said association president Tony Cannavino, who noted that it was the first time a PM had ever addressed a conference of the police association.

Harper told about 150 front-line police personnel representing 54,000 members that his government will scrap the former Liberal government's draft legislation to decriminalize the possession of small amounts of marijuana.

The bill would have allowed people found with small amounts of the drug to avoid a criminal record. They would have instead faced fines.

Harper received sustained applause when he spoke of his government's intention to repeal the so-called faint hope clause – a section of the Criminal Code that allows a criminal serving a life sentence to apply for early parole.

"I thought we might find a responsive audience here," the PM quipped.

Both Harper, and Justice Minister Vic Toews, who also addressed the gathering, promised to find a way to put more officers on the street.

Harper said his government will fund the initiative through cost-sharing programs with municipalities and savings from scrapping the federal gun registry.

Toews said he was proud to say that his first public speech on justice issues as minister of justice was being delivered to the association.

"As always, your opinions and expertise are greatly valued," he said.

The issue of crime is one of the five priorities the newly elected Conservative government has targeted for the legislative session that begins Monday. Ethics, health care, tax cuts and child care round out the agenda.