OTTAWA — As Conservatives pounced on Justin Trudeau's admission he smoked marijuana as an MP, saying it is proof he is unfit to govern, Liberal MPs say they believe the public wants an open and honest leader.

Justice Minister Peter MacKay denounced what he called a "profound lack of judgment" from the Liberal leader.

"By flouting the laws of Canada while holding elected office, he shows he is a poor example for all Canadians, particularly young ones," MacKay said in a statement. "Justin Trudeau is simply not the kind of leader our country needs."

Liberal Senator James Cowan defended Trudeau, calling MacKay’s comments "ridiculous."

"I don’t think that many Canadians will criticize Justin Trudeau for that, and will hold it against that he did what he did, or that he was honest enough to (say it)," the Liberal Senate leader said. "I think Mr. [Stephen] Harper could take a lesson in openness and candour."

Cowan said he thinks people who are turned off by politics will find Trudeau’s comments refreshing.

The NDP leader's office told HuffPost Canada late Thursday afternoon that Thomas Mulcair has not smoked marijuana since he was elected to office. He was elected to National Assembly of Quebec in 1994.

In an interview, NDP justice critic Françoise Boivin suggested elected officials should uphold the law rather than admit to flouting it.

"I'm sure there will be kids saying, 'Hey if he does it, we can do it.'"

She said Trudeau’s policy on marijuana has been difficult to follow and accused him of coming out with a popular stance to lure younger voters.

"It's more an attention grabber than a serious position," she said. The NDP supports decriminalizing possession of marijuana, while Trudeau moved to support the legalization of pot last November.

In an exclusive interview with The Huffington Post Canada, Trudeau said he last smoked marijuana about three years ago at his home in Montreal.

"We had a few good friends over for a dinner party, our kids were at their grandmother's for the night, and one of our friends lit a joint and passed it around. I had a puff," he said.

Trudeau told HuffPost he’s smoked pot five or six times in his life. "It has never really done anything for me," he said. "When the joint went around the room, I usually passed it around to the next person," he said.

"(But) sometimes throughout my life, I’ve had a pull on it."

When asked about Trudeau’s revelation, Harper, who is in Rankin Inlet, Nunavut, on his annual summer tour of northern Canada, said: "For Mr. Trudeau, I think those actions speak for themselves and I don’t have anything to add."

Story continues below slideshow

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  • In 2009, rookie MP Justin Trudeau votes for Bill C-15, which would have <a href="" target="_blank">imposed mandatory minimum sentences for marijuana-related offences. </a> The legislation passes the House of Commons with the support of both Tories and Liberals but dies after Parliament is prorogued.

  • In July of 2009, Trudeau is called a "f**cking hypocrite" by marijuana activist, the so-called "Prince of Pot" Marc Emery, who <a href="" target="_blank">claims the Liberal MP smoked cannabis with him four or five times</a>. "It really pisses me off when I see Justin Trudeau, who took big gaggers with me, is in Parliament actually voting for Bill C-15," Emery says.

  • In May of 2010, Trudeau tells Maclean's magazine that marijuana decriminalization is a step in the wrong direction. "It's not your mother's pot," <a href="" target="_blank">he tells Mitchel Raphael</a> of the stronger marijuana grown today. "I lived in Whistler for years and have seen the effects. We all need our brain cells to deal with our problems."

  • In an <a href="" target="_blank">interview with ProjectRedDot</a> from the floor of the 2012 Liberal Convention in January, Trudeau says he understands pot is not as dangerous as other legal products like alcohol or tobacco, but expresses concern marijuana still "disconnects" you from the world. "So I don’t know that legalizing it – although I totally understand the arguments around removing the criminal elements – I don’t know that it’s entirely consistent with the society we’re trying to build," he says.

  • Seventy-seven per cent of delegates at the 2012 Liberal convention tell the party's leadership they want a future Liberal government to legalize marijuana. "Frankly, the status quo doesn't work and that's what needs to change," says <a href="" target="_blank">interim Grit leader Bob Rae</a>. "The Liberal party is saying that the current laws do not work and that we need a new direction."

  • In November of 2012, not long after launching his leadership bid, Trudeau tells a group of Charlottetown high school students he is a <a href="" target="_blank">"huge supporter" of marijuana decriminalization.</a> "I think we have to recognize first and foremost that the war on drugs, as it exists right now, doesn’t work," he says, adding that the next logical step may be legalization.

  • In January of 2013, Trudeau <a href="" target="_blank">tells a crowd in Red Deer</a> that he would seek the full legalization of marijuana in order to tax and regulate it, making it more difficult for young people to access. "When it's illegal and only available in the black market, someone pushing it doesn't check for ID," Trudeau says.

  • In April of 2013, Trudeau speaks to party members at the Liberal leadership showcase. His speech, <a href="" target="_blank">titled "Hope and Hard Work," </a>makes no mention of his marijuana policies but does attack the Tory tough-on crime agenda. "The Conservatives have forgotten about the value of service," he says. "The only time they talk about community service these days is when it's punishment for a crime."

  • About a week later, Trudeau <a href="" target="_blank">wins the Liberal leadership</a> with more than 80 per cent of the vote. His victory speech makes no mention of pot.

  • In July of 2013, Trudeau's pot remarks to a group of potential British Columbia voters <a href="" target="_blank">quickly go viral</a>. "I'm actually not in favour of decriminalizing cannabis -- I'm in favour of legalizing it. Tax and regulate. It's one of the only ways to keep it out of the hands of our kids because the current war on drugs, the current model isn't working," <a href="" target="_blank">he says</a>.

  • In July of 2013, Trudeau tweets that marijuana prohibition is "costly and unsafe."

  • In August of 2013, Trudeau Liberals launch <a href="" target="_blank">an online petition</a> calling for an end to marijuana prohibition. "Liberals believe in a smart on crime approach, targeting real criminals instead of ordinary Canadians," it reads.

  • UP NEXT: Gorgeous Shots Of Marijuana

  • Look at the little hairs, man

  • Like a Christmas Tree

  • I

  • Purple haze

  • Squid weed?

  • Smoke 'em if ya got 'em

  • This one is intimidating

Vancouver Liberal MP Hedy Fry told HuffPost she’s always believed honesty does not hurt people.

"When people are looking at a leader of a political party or a member of Parliament or an elected official, I think that people want to know that that person is prepared to be honest with the public, and let the public make the decision," she said.

PEI Liberal MP Lawrence MacAulay said Canadians are ready for a politician who speaks openly but expects the Conservative machine to charge.

"They’ll attack him as they always have because he’s a threat to their leadership."

Fellow Liberal PEI MP Sean Casey said his leader's comments would be used against him but he believed it was a gamble worth taking.

"The usual suspects will seize this, and will probably use it to raise money," Casey, the party’s justice critic, said. “But I frankly, don’t think it’s going to work. I think that the general public aren’t on the same page as the Conservatives on this, and it will be a little bit like the frenzy they tried to create about him taking off his shirt [for a charity auction]."

Casey said Trudeau has been remarkably transparent, first by disclosing his finances and now his experience with marijuana.

"He has consistently said that he wants to do politics differently and the general public has been turned off by how politics has been done -- I honestly think this is a calculated gamble that will work. People are ready for it," Casey added.

Earlier on HuffPost:

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  • Barack Obama

    President Barack Obama has admitted to smoking marijuana and using cocaine <a href="">during his high school and college days</a>. "When I was a kid, I inhaled often," <a href="">he once told magazine editors, according to The New York Times</a>. "That was the point."

  • Steve Jobs

    Apple co-founder Steve Jobs' use of LSD in his younger days is well-documented. He once called the experience <a href="">"one of the most important things in my life."</a> His use of the drug was even noted in an <a href="">FBI background check</a>, according to Wired.

  • Bill Clinton

    President Bill Clinton famously admitted to trying marijuana while completing his Rhodes scholarship at Oxford. "When I was in England I experimented with marijuana a time or two, and I didn’t like it," <a href="">The New York Times reported in 1992</a>. "I didn’t inhale it, and never tried it again.”

  • Richard Branson

    Virgin Group chairman and founder <a href="">Richard Branson is an outspoken advocate of marijuana legilization</a>, once writing an op-ed for CNN that called for an end to the war on drugs. He reportedly asked <a href="">President Obama during a White House visit if he could "have a spliff"</a> in 2012. "They didn't have any," he added.

  • Michael Bloomberg

    New York City Mayor and Bloomberg L.P. founder Michael Bloomberg found himself in hot water when he admitted to smoking marijuana back in 2002, The New York Times reports. When asked by a reporter if he had ever tried pot, he responded: <a href="">"You bet I did. And I enjoyed it."</a>

  • Hugh Hefner

    Playboy founder Hugh Hefner credits his use of marijuana later in life with changing his perspective on sex. "I didn't know what making love was all about for all those years," Hefner <a href="">who supports legalization</a> is quoted as saying in <em><a href="">High In America: The True Story Behind NORML</a></em>. <a href="">"Smoking helped put me in touch with the realm of the senses."</a>

  • George Soros

    Billionaire investor George Soros is a known supporter of marijuana legalization and even wrote a 2010 Wall Street Journal op-ed rather straight-forwardly entitled <a href="">"Why I Support Legal Marijuana."</a> His <a href="">use of the drug may be far less proflific</a>, however. He told Reuters in 1997 that while he had "enjoyed" trying marijuana, <a href="">"it did not become a habit and I have not tasted it in many years."</a>

  • Jimmy Cayne

    Jimmy Cayne, former CEO of Bear Stearns, kept an<a href=""> antacid bottle full of cocaine</a> in his desk, according to the book <a href="">The Sellout</a>.

  • Sarah Palin

    The former vice presidential candidate and reality TV star told Anchorage Daily News back in 2006 that she couldn't <a href="">"claim a Bill Clinton and say that I never inhaled,”</a> CBS News reports.

  • Bill Gates

    Bill Gates, chairman and co-founder of Microsoft, hinted at once using LSD and marijuana in a <a href="">1994 interview with Playboy</a>. Likewise, <a href="">biographer Stephen Manes</a> wrote that "<a href="">Gates was certainly not unusual there</a> [around drugs]. Marijuana was the pharmaceutical of choice…”

  • Larry Kudlow

    Former Ronald Reagan economic adviser and current CNBC host Larry Kudlow is reported to have both smoked marijuana and <a href="">used cocaine frequently</a> at periods in his life. After being fired from Bear Sterns in the mid-1990s, <a href="">Kudlow entered a rehabilitation program to deal with his cocaine addiction</a>, according to New York Magazine.

  • Naomi Campbell

    Super model Naomi Campbell <a href="">admitted in 2005 to abusing cocaine during her career</a>. "I have admitted using illegal drugs and some years ago I recognised that I had a problem" <a href="">she was quoted as saying in The Daily Mail.</a> "I knew that it was wrong and had damaged me and I decided to try and sort myself out."

  • Peter Lewis

    Peter Lewis, former CEO of Progressive Insurance, has both <a href="">smoked marijuana and lobbied heavily for its legalization</a>. After smoking weed recreationally in his youth, he started using it medicinally after his leg was amputated. “<a href="">I was very glad I had marijuana,"</a> he told Boston Magazine. "It didn’t exactly eliminate the pain, but it made the pain tolerable — and it let me avoid those heavy-duty narcotic pain relievers that leave you incapacitated.”

  • Arnold Schwarzenegger

    Former California Governor and all around legend Arnold Schwarzenegger can be seen smoking marijuana in the 1977 documentary "Pumping Iron." He later said that he <a href="">"did smoke a joint and I did inhale,"</a> CBS News reports.

  • Bernie Madoff

    In a 2009 lawsuit, it was alleged that Ponzi schemer Bernie Madoff frequently sent messengers to buy cocaine for <a href="">"himself and the company."</a> Actually, before Madoff's $60 billion Ponzi scheme fell apart, his office was known as <a href="">"the North Pole"</a> because of the allegedly excessive cocaine use during work hours, according to CNN.

  • Aldous Huxley

    Essayist and author Aldous Huxley is said to have experimented with hallucinogenics, even writing an account of his use of mescaline in <a href="">"The Doors Of Perception."</a>

  • Al Gore

    Former Vice President and climate change activist Al Gore is rumored to have smoked marijuana often in college. However, Gore characterized his marijuana use as <a href="">"infrequent and rare,"</a> according to The Guardian.

  • Maya Angelou

    Best-selling author Maya Angelou reportedly <a href="">"settled into a job as a waitress and began smoking marijuana with abandon"</a> early in her life, <a href="">according to a biography by Harold Bloom and Cindy Dyson</a>.

  • Ted Turner

    CNN founder and Atlanta Braves owner <a href="">Ted Turner is rumored</a> to have grown pot in his college dorm room, according to COED Magazine (he's reportedly also a major donor to the Kentucky Hemp Museum). After banning cigarette smoking at CNN in the early '90s, a memo emerged that claimed it <a href="">"was common knowledge that Turner sits in his office and smokes marijuana."</a>

  • Clarence Thomas

    Supreme Court Justice Clarence Thomas smoked marijuana <a href="">"several times"</a> in college, White House spokesman Judy Smith said back in 1991.

  • Kary Mullis

    Nobel Prize-winning chemist <a href="">Kary Mullis credited much of his success to his use of LSD</a>, according to Wired.

  • Next: Celebrities Who Have Used Drugs

  • Angelina Jolie

    "I have done just about every drug possible: cocaine, ecstasy, LSD and, my favorite, heroin." [The Mirror, 1996]

  • George Clooney

    "I didn't live my life in the right way for politics, you know. I fucked too many chicks and did too many drugs, and that's the truth. That's gonna be my campaign slogan: 'I drank the bong water.'" [Newsweek, 2011]

  • Whoopi Goldberg

    <em>On smoking a joint to calm herself before winning her 1991 Oscar for "Ghost":</em> "Smoking cigarettes and pot every now and then are my habits. And so I thought, 'I've got to relax.' So I smoked this wonderful joint that was the last of my homegrown. And honey, when [Denzel Washington] said my name and I popped up, I thought, 'Oh, fuck.'"

  • Sienna Miller

    "I mean, I still love a waterfall or the odd hallucinogenic drug. I liked mushrooms, which were legal until a year or so ago. If I had a drug of choice, it would be magic mushrooms." [The Guardian, 2007]

  • Megan Fox

    "I’ve done drugs, and that’s how I know I don’t like them. Cocaine is back with a vengeance. Everyone in every club is doing drugs. A lot of people are on prescription drugs. Celebrities aren’t trying to hide it, except where people have camera phones. ... I wanted to try several things and make an informed decision, but I didn’t enjoy anything other than marijuana. I don’t even think of it as a drug -- it should be legalized. I know about five people who aren’t on drugs today, and I’m one of them." [Maxim, 2007]

  • Joel Madden

    “Without cigarettes, I would be doing heroin, probably, on a daily basis.” [Blender, 2007]

  • Oprah Winfrey

    <em>On doing cocaine with her boyfriend in the '70s while working as an anchorwoman in Nashville:</em> "I did your drug. This is probably one of the hardest things I have ever said. ... I had a perfect, round, little Afro, I went to church on Sunday and I went to Wednesday prayer meetings when I could ... and I did drugs." ["The Oprah Winfrey Show," 1995]

  • Anthony Kiedis

    "I spent most of my life looking for the quick fix and the deep kick. I shot drugs under freeway off-ramps with Mexican gangbangers and in thousand-dollar-a-day hotel suites. Now I sip vitamin-infused water and seek out wild, as opposed to farm-raised, salmon." ["Scar Tissue," published 2005]

  • Drew Barrymore

    "When I was 10 ½, I was sitting in a room with a group of young adults who were smoking pot. I wanted to try some, and they said, 'Sure. Isn't it cute, a little girl getting stoned?' Eventually that got boring, and my addict mind told me, 'Well, if smoking pot is cute, it'll also be cute to get the heavier stuff like cocaine.' It was gradual. What I did kept getting worse and worse, and I didn't care what anybody else thought." [People, 1989]

  • Nicole Richie

    "I kind of took matters into my own hands and was creating drama in a very dangerous way. I think I was just bored, and I had seen everything. Especially when you're young, you just want more. ... At 18 I had just been doing a lot of cocaine." [People, 2007]

  • George Michael

    "[Marijuana] keeps me sane and happy. I could write without it if I was sane and happy. ... This is the only kind of drug I ever thought worth taking." [ITV's "South Bank Show," 2008]

  • Morgan Freeman

    "Never give up the ganja." [The Guardian, 2003]

  • Kirsten Dunst

    "I've never been a major smoker, but I think America's view on weed is ridiculous. I mean, are you kidding me? If everyone smoked weed, the world would be a better place." [The Daily Mail, 2007]

  • Elton John

    "I was consumed by cocaine, booze and who knows what else. I apparently never got the memo that the Me generation had ended." ["Love Is the Cure: On Life, Loss and the End of AIDS," published 2012]

  • Frances McDormand

    “I’m a recreational pot-smoker. ... There has never been enough of a distinction between marijuana and other drugs. In the classic, weird hygiene movies from high school, everything led to depravity -- marijuana, sex, coffee! There was no distinction made between the effects of one thing. So it’s always been lumped in with drugs in general. It’s a human rights issue, a censorship issue and a choice issue." [High Times, 2003]

  • Dennis Quaid

    “Cocaine was even in the budgets of movies, thinly disguised. It was petty cash, you know? It was supplied, basically, on movie sets because everyone was doing it. People would make deals. Instead of having a cocktail, you’d have a line." [Newsweek, 2011]

  • Nicolas Cage

    "I had a bag of mushrooms in my refrigerator. My cat used to sneak into the refrigerator and eat them. ... He ate them voraciously; it was like catnip to him. So I thought, 'What the heck, I better do it with him.' I remember lying on my bed for hours and Lewis was on the desk across my bed for hours, and we just stared at each other -- not moving, just staring at each other, and I had no doubt that he was my brother. But having said that, I don't do that anymore. And you know what? Later in life, when I was completely not doing any of that, I know he said 'Hi' to me." ["Late Show With David Letterman," 2010]

  • Johnny Depp

    "I don't trust anyone who hasn't been self-destructive in some way. Who hasn't gone through some sort of bout of self-loathing. You've got to bang yourself around a bit to know yourself." [GQ, 2011]

  • Frank Ocean

    "hi guys, i smoke pot. ok guys, bye." [Twitter, 2013]

  • Fergie

    “I got into a scene. I started going out and taking ecstasy. From ecstasy, it went to crystal meth. With any drugs, everything is great at the beginning, and then slowly your life starts to spiral down. [I was] 90 pounds at one point.” ["Oprah's Next Chapter," 2012]