Justin Trudeau's widely publicized revelations of pot use may force him to pull a U-turn at the U.S. border, says a lawyer who's had clients in similar situations.

But it's not just the Liberal leader who faces this potential dilemma.

Immigration lawyer Len Saunders told The Huffington Post Canada that Trudeau, and any other Canadians who have been open about smoking marijuana, can expect to be turned back at the border.

In August, Trudeau told HuffPost he dabbled with a doobie after becoming an MP. And although the candid confession netted him plenty of praise from the public and his own party, it also drew flak from the Harper government.

Federal Justice Minister Peter MacKay was quick to pounce, saying the Liberal leader set a "poor example" by breaking the law. However, an Ottawa-based law professor accused MacKay of misleading the public, pointing out that while is illegal to grow, traffic or possess marijuana, smoking pot is not a criminal offence.

Still, Saunders said that not only is merely admitting to smoking pot in the past a magnet for trouble — even if there weren't any convictions, arrests or charges — but any online evidence of an admission could be used to deny a Canadian entry across the border.

That puts other Canadian politicians who disclosed their own past puffing after Trudeau's admission — from Toronto Mayor Rob Ford to Nova Scotia Premier Darrell Dexter — in the same "inadmissible" boat as Trudeau.

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  • Rob Ford

    Toronto Mayor Rob Ford says he has had his <a href="http://www.huffingtonpost.ca/2013/08/28/rob-ford-marijuana-wynne_n_3831389.html" target="_blank">fair share of marijuana</a>. "Oh, yeah. I've smoked a lot of it."

  • Justin Trudeau

    The federal Liberal leader opened up to HuffPost about his experience with marijuana in August. "Sometimes, I guess, I have gotten a buzz, but other times no. I’m not really crazy about it.”

  • Tom Mulcair

    The Opposition leader's office told HuffPost this summer that Mulcair <a href="http://www.huffingtonpost.ca/2013/08/22/justin-trudeau-marijuana-peter-mackay_n_3797481.html" target="_blank">has smoked in the past</a> but not since he was elected to office. Mulcair was elected to the National Assembly of Quebec in 1994.

  • Jim Flaherty

    Said the <a href="http://www.mapinc.org/drugnews/v02/n506/a09.html" target="_blank">Tory finance minister</a>: "Yeah, in my teenage years... a couple of times, I have to admit: I didn’t like it."

  • Marc Garneau

    The Liberal MP and Canada's first astronaut said he tried marijuana as a <a href="http://www.cbc.ca/player/News/Politics/Power+%26+Politics/ID/2402495133/" target="_blank">student in the 1970s in England. </a> "It's not my thing. I stopped because it wasn't doing anything for me."

  • Kathleen Wynne

    The premier of Ontario said she <a href="http://www.huffingtonpost.ca/2013/08/28/kathleen-wynne-marijuana-pot_n_3830736.html?utm_hp_ref=canada-politics" target="_blank">smoked pot decades ago</a>. "I have smoked marijuana but not for the last 35 years."

  • Darrell Dexter

    Said the <a href="http://www.huffingtonpost.ca/2013/08/29/darrell-dexter-marijuana-pot_n_3837009.html?utm_hp_ref=canada-politics" target="_blank">former premier of Nova Scotia</a>: "Like every other person I knew back in the '70s when I went to university, some of whom are actually in this room, I would have tried it, the same as other people at that time."

  • Christy Clark

    Said the <a href="http://www.huffingtonpost.ca/2012/05/01/christy-clark-marijuana-use-pot_n_1469321.html" target="_blank">premier of British Columbia</a>: "I graduated from Burnaby South Senior Secondary in 1983 and there was a lot of that going on when I was in high school and I didn't avoid it all together."

  • Tim Hudak

    The leader of the Progressive Conservative Party of Ontario admitted he's <a href="http://www.thestar.com/news/canada/2011/08/18/hudak_admits_to_smoking_pot.html" target="_blank">puffed in the past.</a> "I was a normal kid, I had a normal upbringing, a normal life in university. I experimented from time to time with marijuana. It’s a long time ago in the past and in the grand scheme of things."

  • Paul Martin

    The former prime minister of Canada <a href="http://www.ctvnews.ca/" target="_blank">told CTV News</a>: "The answer is: I never smoked. I never smoked anything, but there was an earlier time, years ago, when (my wife) made some brownies and they did have a strange taste."

  • Kim Campbell

    The former prime minister admitted while running for the leadership of the Progressive Conservatives that <a href="http://fullcomment.nationalpost.com/2013/08/22/chris-selley-trudeau-pot-revelation-underscores-one-of-his-few-actual-policy-positions/" target="_blank">she tried weed.</a> "And I inhaled the smoke."

  • Jack Layton

    Said the former NDP leader: "Yes, and some might say I never exhaled."

  • Dalton McGuinty

    The former premier of Ontario said he <a href="http://www.cfdp.ca/cita99.htm" target="_blank">experimented in his teens</a>, but only twice.

  • Brad Wall

    The premier of Saskatchewan said he was an <a href="http://www.canada.com/topics/news/politics/story.html?id=f23471e8-be96-46cf-9c1f-b43d5c497cdd" target="_blank">"infrequent" user back in university.</a> "It didn't really do anything for me, luckily, because for some, it does lead to other things."

  • UP NEXT: Celebs Smoking Pot

  • Snoop Dogg

    The rapper's 18-year-old son, Corde Calvin Broadus, caused a stir when he <a href="http://www.digitalspy.com/celebrity/i435058-16/twitterinstagram-pics-of-2012-snoop-dogg-and-son-corde-calvin-broadus.html">shared this photo of him</a> smoking with his famous weed-loving dad.

  • Soulja Boy, Wiz Khalifa

    Is that smoke, or a new Instagram filter? Soulja Boy<a href="http://www.huffingtonpost.com/2013/01/03/soulja-boy-wiz-khalifa-smoke-up-photo_n_2402221.html"> tweeted a photo </a>of what appears to be him and pal Wiz Khalifa smoking out a giant bong on Jan. 3.

  • Chris Brown

    "Oh don't worry," Brown wrote on this <a href="http://instagram.com/p/SzQdSKPpVR/">Instagram photo </a>he shared in December, from Amsterdam. "It's medicinal!! Lol."

  • Kristen Stewart

    <a href="http://www.vanityfair.com/online/daily/2012/06/kristen-stewart-responds-critics-shit-eaters-vanity-fair">In a 2012 Vanity Fair article</a>, Stewart addressed the photos taken of her smoking out of a pipe in 2008. "You can Google my name and one of the first things that comes up is images of me sitting on my front porch smoking a pipe with my ex-boyfriend and my dog," she said. "I was a kid. I had just turned 18. In [the tabloids] the next day it was like I was a delinquent slimy idiot, whereas I’m kind of a weirdo, creative Valley Girl who smokes pot. Big deal.”

  • Rihanna

    Dressing up as <a href="http://www.huffingtonpost.com/2012/11/02/rihanna-topless-singer-post-halloween-lok_n_2066153.html">"The Bride of Mary Jane"</a> (get it?) for Halloween wasn't enough. Rihanna shared this controversial picture at the start of the New Year, with the caption: "This nug look like a skull or am I just....?"

  • Miley Cyrus

    A video of <a href="http://www.tmz.com/2010/12/10/miley-cyrus-video-bong-hit-smoking-salvia-herb-pyschedelic-birthday-party-hannah-montana/">Miley Cyrus partying with a bong </a>just after her 18th birthday became instant tabloid fodder when it hit the internet in 2010. Her reps say that she was actually smoking the herb salvia.

  • Michael Phelps

    Yup. That's Olympic Gold medalist <a href="http://sports.espn.go.com/oly/swimming/news/story?id=3876804">Michael Phelps smoking out of a bong</a>, published in the now-defunct British rag News of the World in 2009.

  • Lady Gaga

    Lady Gaga smoked a spliff onstage at a concert in -- duh -- Amsterdam. About marijuana, <a href="http://www.huffingtonpost.com/2012/09/19/lady-gaga-weed-singer-wondrous-marijuana_n_1897486.html">she told the audience</a>: "I want you to know it has totally changed my life and I've really cut down on drinking. It has been a totally spiritual experience for me with my music."

  • Justin Bieber

    Last week, <a href="http://www.huffingtonpost.com/2013/01/05/justin-bieber-smoking-pot-photos-emerge-teen-star-partying_n_2415401.html">photos emerged </a>of what appears to be Bieber smoking marijuana inside a Newport Beach hotel room on Jan. 2. "Everyday growing and learning. trying to be better. u get knocked down, u get up," Bieber tweeted not long after the reports trickled through. "Back on tour tomorrow. ready to see u all smile. time to do what im supposed to be doing. performing. #BELIEVEtour."

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  • Barack Obama

    President Barack Obama has admitted to smoking marijuana and using cocaine <a href="http://www.nytimes.com/2008/02/09/us/politics/09obama.html?pagewanted=all&_r=0">during his high school and college days</a>. "When I was a kid, I inhaled often," <a href="http://www.nytimes.com/2006/10/24/world/americas/24iht-dems.3272493.html">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="http://www.thefiscaltimes.com/Articles/2011/10/24/Steve-Jobs-10-Revealing-Quotes-from-His-Biography.aspx#zqEbfO6jmqxtvYKB.99">"one of the most important things in my life."</a> His use of the drug was even noted in an <a href="http://www.wired.co.uk/news/archive/2012-02/10/steve-jobs-fbi">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="http://www.nytimes.com/1992/03/30/us/the-1992-campaign-new-york-clinton-admits-experiment-with-marijuana-in-1960-s.html?gwh=B1648339901F9BBAADA0D9EC8C030343">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="http://www.cnn.com/2012/12/06/opinion/branson-end-war-on-drugs">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="http://www.politico.com/news/stories/0312/74111.html">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="http://www.nytimes.com/2002/04/10/nyregion/bloomberg-says-he-regrets-marijuana-remarks.html">"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="http://www.foxnews.com/entertainment/2010/11/23/hugh-hefner-talks-monogomy-miley-cyrus-marijuana/">who supports legalization</a> is quoted as saying in <em><a href="http://www.amazon.com/High-In-America-Politics-Marijuana/dp/0670119903">High In America: The True Story Behind NORML</a></em>. <a href="http://www.druglibrary.org/special/anderson/highinamerica8.htm">"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="http://online.wsj.com/article/SB10001424052702303467004575574450703567656.html">"Why I Support Legal Marijuana."</a> His <a href="http://www.aim.org/special-report/the-hidden-soros-agenda-drugs-money-the-media-and-political-power/">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="http://www.mpp.org/outreach/top-50-marijuana-users-list.html">"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="http://www.businessinsider.com/wall-street-cocaine-stories-2012-7?op=1"> antacid bottle full of cocaine</a> in his desk, according to the book <a href="http://books.google.com/books/about/The_Sellout.html?id=Jq030Cp_SjQC">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="http://www.cbsnews.com/stories/2008/08/29/politics/politico/thecrypt/main4397109.shtml">"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="http://ei.cs.vt.edu/~history/Bill.Gates.html">1994 interview with Playboy</a>. Likewise, <a href="http://www.amazon.com/Gates-Microsofts-Reinvented-Industry-Himself/dp/0671880748">biographer Stephen Manes</a> wrote that "<a href="http://www.mpp.org/outreach/top-50-marijuana-users-list.html">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="http://www.guardian.co.uk/money/2000/nov/29/workandcareers.madeleinebunting">used cocaine frequently</a> at periods in his life. After being fired from Bear Sterns in the mid-1990s, <a href="http://books.google.com/books?id=bOQCAAAAMBAJ&pg=PA38&dq=kudlow+cocaine&ei=VCR0S9XdEpG2NJDq0bsE&cd=1#v=twopage&q&f=true">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="http://www.nbcnews.com/id/7018893/site/todayshow/ns/today-entertainment/t/naomi-campbell-say-she-nearly-self-destructed-because-cocaine/#.USU_XVo6VOg">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="http://www.dailymail.co.uk/news/article-99840/Naomi-confesses-drug-abuse.html#ixzz2LTfhOeI6">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="http://www.forbes.com/sites/clareoconnor/2012/04/20/high-roller-how-billionaire-peter-lewis-is-bankrolling-marijuana-legalization/">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="http://www.bostonmagazine.com/news/blog/2012/07/16/medical-marijuana-question-thank-78-year-billionaire-insurance-executive/">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="http://www.cbsnews.com/2100-207_162-529462.html">"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="http://www.dailymail.co.uk/news/article-1221984/Fraudster-Bernie-Madoff-cocaine-office-dubbed-North-Pole.html">"himself and the company."</a> Actually, before Madoff's $60 billion Ponzi scheme fell apart, his office was known as <a href="http://articles.cnn.com/2009-10-22/justice/madoff.lawsuit_1_bernie-madoff-kpmg-jp-morgan-chase?_s=PM:CRIME">"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="http://www.huffingtonpost.com/2012/04/20/10-celebrity-lsd-users_n_1440786.html">"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="http://www.guardian.co.uk/world/2000/feb/07/uselections2000.usa">"infrequent and rare,"</a> according to The Guardian.

  • Maya Angelou

    Best-selling author Maya Angelou reportedly <a href="http://books.google.com/books?id=uVEK3f8ojJUC&pg=PA16&lpg=PA16&dq=maya+angelou+marijuana+use&source=bl&ots=iiUM7k5Uqw&sig=BlWCUSUqUIHOokcdjr3kA2GVrjg&hl=en&sa=X&ei=BHouUbW_FYm-9QSPooHABw&ved=0CFAQ6AEwAw#v=onepage&q=maya%20angelou%20marijuana%20use&f=false">"settled into a job as a waitress and began smoking marijuana with abandon"</a> early in her life, <a href="http://www.amazon.com/Angelou-Blooms-BioCritiques-Cindy-Dyson/dp/0791061779">according to a biography by Harold Bloom and Cindy Dyson</a>.

  • Ted Turner

    CNN founder and Atlanta Braves owner <a href="http://coedmagazine.com/2009/02/06/the-10-most-successful-potheads-on-the-planet-cool-enough-to-admit-it/">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="http://tobaccodocuments.org/pm/2024271877.html">"was common knowledge that Turner sits in his office and smokes marijuana."</a>

  • Clarence Thomas

    Supreme Court Justice Clarence Thomas smoked marijuana <a href="http://www.nytimes.com/1991/07/11/us/thomas-smoked-marijuana-but-retains-bush-support.html">"several times"</a> in college, White House spokesman Judy Smith said back in 1991.

  • Kary Mullis

    Nobel Prize-winning chemist <a href="http://www.wired.com/science/discoveries/news/2006/01/70015?currentPage=all">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]

"The thing is at some point, [Trudeau] will be asked [and] they'll Google search him. And if you Google search Justin Trudeau right now I'm sure the first thing which comes up is him admitting to drug use," Saunders said.

"Any officer doing his or her job is going to see that and say 'sir, you admitted to using these drugs, is this true'?"

Saunders, a Canadian-born American citizen whose firm is based in Blaine, Washington, said he thinks his clients who were denied entry for their confessions would be "unhappy" if Trudeau was treated differently.

"If everyone is supposed to be treated the same, then he should be denied entry," he said.

Jessica Goldstein is among the most recent Canadians to be denied at the border over a pot-smoking confession.

The 30-year-old university student told the Vancouver Sun she was rejected Saturday at the Douglas border crossing in B.C. for admitting she smoked pot a couple of days earlier.

Andrew Feldmar knows the experience, too. The Canadian psychologist was turned back in 2006, according to Wired, after a border officer Googled his name and found research he had written about experimenting with LSD in the 1960's.

"It's totally unfair, totally unjust," Feldmar told CTV News. "If they stopped everybody who has used illicit substances, nobody would be allowed into the United States."

And if a conviction does exist, it doesn’t matter when it happened.

Myles Wilkinson, a Vancouver Island resident who won an all-expense-paid trip to watch the Super Bowl final last year, was denied entry into the U.S for a marijuana possession conviction from 1981, the CBC reported in February.

"I can't believe that this is happening, for something that happened 32 years ago,” he said.

But there’s a way out. Or in this case, a way in.

Saba Naqvi, a Vancouver-based immigration lawyer, says that while she doesn't believe online search results of Trudeau's admission are grounds for inadmissibility, she "would not be surprised if they told him he needs a waiver to get into the United States."

"Whether they should be permitted to use it or not, that's a whole different question, but they often do use that to determine whether they're going to allow the person admission into the U.S," she said.

Naqvi added the law states border officers must inform individuals of all the "essential elements" of the crime they admit to, meaning the traveller must get an opportunity to explain all the context and circumstances.

She also said travellers who are in urgent need of entry to the U.S. but get denied can get exempted through humanitarian parole.

Saunders agrees any Canadian denied entry must file for a waiver, which costs $585 at the port of entry and anywhere between $500 and $2,000 with a lawyer. Waivers take between six months to a year to be issued, Saunders added, and they aren't evergreen.

Saunders recommends that Canadians travelling to the U.S. understand the difference between federal law and state law, but he sympathizes with those who answer the question truthfully — although he says you are under no obligation to do so.

"What I tell people is there's two Washingtons: there's Washington State, where [pot is] legal, but then there's Washington D.C., where it's not legal, and it's the Washington D.C. that has jurisdiction over these ports of entry," he said.

"What troubles people in situations like this is they're just being honest. They're just being honest, they're answering a question innocently that they think is not going to have, literally, life-time repercussions."

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