Was Hillary Clinton wrong about marijuana research?

Democratic presidential candidate Hillary Clinton addresses supporters during a primary night event on April 26 in Philadelphia after winning the Pennsylvania state primary.

Was Hillary Clinton wrong about marijuana research?

Jake Tapper examines the accuracy of Hillary Clinton's claim that marijuana research is impossible because of its status as a Schedule I drug.

02:41 - Source: CNN

Jake Tapper Factcheck.org 47 videos

Democratic presidential candidate Hillary Clinton addresses supporters during a primary night event on April 26 in Philadelphia after winning the Pennsylvania state primary.

Was Hillary Clinton wrong about marijuana research?

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White House Press Secretary Sean Spicer (L) looks on as US Secretary of Health and Human Service Tom Price (C) takes questions during the daily briefing at the White House in Washington, DC on March 7, 2017. / AFP PHOTO / JIM WATSON (Photo credit should read JIM WATSON/AFP/Getty Images)

Checking Tom Price on the GOP health care plan

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NEW YORK, NY - MARCH 7: A view of Trump Tower, March 7, 2017 in New York City. In a series of tweets on Saturday morning, President Donald Trump accused former President Barack Obama of ordering wiretapping at Trump Tower during the run up to the election. (Photo by Drew Angerer/Getty Images)

Examining Trump's wiretap claim

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WINSTON-SALEM, NC - OCTOBER 27: Democratic presidential nominee former Secretary of State Hillary Clinton looks on as First Lady Michelle Obama speaks during a campaign rally at Wake Forest University on October 27, 2016 in Winston-Salem, North Carolina. With less than two weeks to go before the election, Hillary Clinton is campaigning in North Carolina with First Lady Michelle Obama.

Falsehoods from both sides on the FBI email inquiry

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WASHINGTON, DC - JANUARY 10: Sen. Jeff Sessions (R-AL) is sworn in before the Senate Judiciary Committee during his confirmation hearing to be the U.S. attorney general January 10, 2017 in Washington, DC. Sessions was one of the first members of Congress to endorse and support President-elect Donald Trump, who nominated him for Attorney General. (Photo by Chip Somodevilla/Getty Images)

Did Jeff Sessions lie to Congress?

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Fact check: Trump on undocumented immigrants and voting

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Sen. Bernie Sanders (I-VT), attends a portrait unveiling ceremony for outgoing Senate Minority Leader Harry Reid (D-NV), on Capitol Hill December 8, 2016 in Washington, DC.

Checking Bernie Sanders on confirmation precedent

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Democratic presidential nominee former Secretary of State Hillary Clinton listens to Republican presidential nominee Donald Trump speak during the third U.S. presidential debate at the Thomas & Mack Center on October 19, 2016 in Las Vegas, Nevada.

Fact check: Clinton's on the 2008 'Heller' decision

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WASHINGTON, DC - JANUARY 31: U.S. President Donald Trump (C) arrives for a meeting with Homeland Security Secretary John Kelly (2nd L), National Security Advisor Michael Flynn, White House Government Initiatives Director Reed Cordish and other government cyber security experts in the Roosevelt Room at the White House January 31, 2017 in Washington, DC. Citing the hack of computers at the Democratic National Committee by Russia, Trump said that the private and public sectors must do more to prevent and protect against cyber attacks. (Photo by Chip Somodevilla/Getty Images)

Fact-checking Trump on his Iraq refugee claims

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Voting booths set up inside a polling station in Christmas, Florida on November 8, 2016.

Fact-checking Trump's claims on voter fraud

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TOPSHOT - Republican nominee Donald Trump gestures as Democratic nominee Hillary Clinton looks on during the final presidential debate at the Thomas & Mack Center on the campus of the University of Las Vegas in Las Vegas, Nevada on October 19, 2016. / AFP / Mark RALSTON (Photo credit should read MARK RALSTON/AFP/Getty Images)

4 fact checks from the final presidential debate

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Democratic presidential nominee former Secretary of State Hillary Clinton and Republican presidential nominee Donald Trump speak during the town hall debate at Washington University on October 9, 2016, in St. Louis.

7 fact checks from the town hall presidential debate

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4 misleading lines from a single Hillary Clinton speech

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4 Trump whoppers from a single stump speech

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US Secretary of State Hillary Clinton (R) shakes hands with Russian Prime Minister Vladimir Putin (L) outside Moscow in Novo-Ogarevo on March 19, 2010. Russian Prime Minister Vladimir Putin met US Secretary of State Hillary Clinton and used the occasion to bemoan Moscow's stalled WTO application and the state of bilateral trade. Russia, the world's largest economy outside the global trade body, has repeatedly accused Washington of hindering its efforts to join the World Trade Organization in talks that have dragged on since 1993.

Clinton Ad Misleads on Russian Nuclear Agreement

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Ivanka Trump looks on as her her father, Republican presidential hopeful Donald J. Trump, speaks during a campaign event at the Aston Township Community Center on September 13, 2016 in Aston, Pennsylvania.

Ivanka wrong on Trump company's maternity leave policy

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PHILADELPHIA, PA - JULY 28: Democratic presidential nominee Hillary Clinton acknowledges the crowd as she arrives on stage during the fourth day of the Democratic National Convention at the Wells Fargo Center, July 28, 2016 in Philadelphia, Pennsylvania. Democratic presidential candidate Hillary Clinton received the number of votes needed to secure the party's nomination. An estimated 50,000 people are expected in Philadelphia, including hundreds of protesters and members of the media. The four-day Democratic National Convention kicked off July 25. (Photo by Jessica Kourkounis/Getty Images)

Fact checking Clinton's public statements on her emails

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Secretary of State Hillary Clinton arrives to speak on September 12, 2012, on the killing of US Ambassador to Libya Christopher Stevens and 3 staff members at the U.S. Consulate building in Benghazi, Libya, from the U.S. Department of State.

Hillary Clinton's public and private Benghazi remarks

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A multi-point fact check of Trump's anti-Clinton speech

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Republican presidential candidate Donald Trump speaks during a rally in Fresno, California on May 27, 2016. / AFP / JOSH EDELSON (Photo credit should read JOSH EDELSON/AFP/Getty Images)

Trump's 'fishy' statements on the drought in California

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Hillary Clinton claims Trump wants to 'abolish' the VA

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VANDALIA, OH - MARCH 12: Republican Presidential candidate gives a thumbs up to the crowd walking off his plane at a campaign rally on March 12, 2016 in Vandailia, Ohio. Today was the first rally after violence broke out in a Trump Rally in Chicago yesterday which canceled the rally. (Photo by Ty Wright/Getty Images)

Checking Trump's argument against releasing his taxes

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Fact Check: Hillary Clinton still spinning emails

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CHICAGO - DECEMBER 01: President-elect Barack Obama (L) introduces Senator Hillary Clinton (D-NY) as his choice for secretary of state during a press conference at the Hilton Hotel December 01, 2008 in Chicago, Illinois. Other members of the National Security Team named by Obama at the press conference include Washington attorney Eric Holder as attorney general, Arizona Governor Janet Napolitano as his choice for homeland security and he said Robert Gates would remain as defense secretary. Retired Marine Gen. James L. Jones was selected for the position of national security adviser and Susan Rice as U.N. ambassador. (Photo by Scott Olson/Getty Images)

Hillary Clinton did not start the 'birther' movement

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Is Ted Cruz an 'outsider' like Bernie Sanders?

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BRIDGETON, MO - NOVEMBER 12: Customers shop for a handgun at Metro Shooting Supplies on November 12, 2014 in Bridgeton, Missouri. The suburban St. Louis store is located near Ferguson, Missouri where several weeks of sometimes violent protests erupted following the shooting death of Michael Brown by Ferguson police officer Darren Wilson on August 9th. The gun shop last week experienced a 300 percent increase in sales over the same period last year. About 60 percent of those sales were from first-time gun owners. The increase is attributed in part to concern from residents of additional outbreaks of violence if the grand jury investigating Brown's death does not find justification to prosecute Wilson for the shooting. The grand jurys decision is expected sometime in November. (Photo by Scott Olson/Getty Images)2

How many of New York's seized guns began in Vermont?

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PHILADELPHIA, PENNSYLVANIA - APRIL 07: Democratic presidential candidate Sen. Bernie Sanders (D-VT) speaks during the AFL-CIO Convention at the Downtown Sheraton Philadelphia on April 7, 2016 in Philadelphia, Pennsylvania. The Pennsylvania primaries will be held on April 26. (Photo by William Thomas Cain/Getty Images)

How transparent is Bernie Sanders on his tax returns?

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CEDAR RAPIDS, IA - FEBRUARY 1 : Republican presidential candidate Donald Trump speaks with his wife Melania Trump by his side during a campaign event at the U.S. Cellular Convention Center February1, 2016 in Cedar Rapids, Iowa. Trump who is seeking the nomination for the Republican Party attends his final campaign rally ahead of tonight's Iowa Caucus. (Photo by Joshua Lott/Getty Images)

Did Cruz use a photo of Trump's wife in an attack ad?

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Did Bernie Sanders take money from Wall Street?

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Ted Cruz participates in a CNN South Carolina Republican Presidential Town Hall on February 17, 2016, in Greenville, South Carolina.

Fact-checking Ted Cruz on same-sex marriage ruling

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MANCHESTER, NH - FEBRUARY 09: Republican presidential candidate Donald Trump speaks after Primary day at his election night watch party at the Executive Court Banquet facility on February 9, 2016 in Manchester, New Hampshire. Trump was projected the Republican winner shortly after the polls closed. (Photo by Joe Raedle/Getty Images)

Checking Donald Trump's claim of a 42% unemployment rate

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Ted Cruz and Marco Rubio talk after a Republican presidential primary debate, Thursday, Jan. 28, 2016, in Des Moines, Iowa. (AP Photo/Chris Carlson)

Checking Ted Cruz's attacks on Rubio and immigration

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Fact Checking Trump on Iran and Clinton on Medicare

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State of the Union fact check

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SALT LAKE CITY, UT - JANUARY 15: Brett Nielsen fires an Glock handgun at the "Get Some Guns & Ammo" shooting range on January 15, 2013 in Salt Lake City, Utah. Lawmakers are calling for tougher gun legislation after recent mass shootings at an Aurora, Colorado movie theater and at Sandy Hook Elementary School in Newtown, Connecticut. (Photo by George Frey/Getty Images)

Checking Barack Obama, Jeb Bush and Marco Rubio on guns

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The top campaign whoppers from a lie-filled 2015

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Are 700,000 Americans on 'some watch list or another'

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Checking Hillary Clinton's claims on mortality study

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Republican presidential candidate Ben Carson speaks during a Distinguished Speakers Series event at Colorado Christian University on October 29, 2015 in Lakewood, Colorado.

Checking Ben Carson's claim of 'extreme political bias'

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BOULDER, CO - OCTOBER 28: Presidential candidates Donald Trump (L) speaks while Ben Carson looks on during the CNBC Republican Presidential Debate at University of Colorados Coors Events Center October 28, 2015 in Boulder, Colorado. Fourteen Republican presidential candidates are participating in the third set of Republican presidential debates. (Photo by Justin Sullivan/Getty Images)

Factchecking the frontrunners at the CNBC debate

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Fact checking Joe Biden's new retelling of the Osama Bin Laden raid

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LAS VEGAS, NV - OCTOBER 13: (L-R) Democratic presidential candidates Sen. Bernie Sanders (I-VT) Hillary Clinton and Martin O'Malley walk on the stage at the end of a presidential debate sponsored by CNN and Facebook at Wynn Las Vegas on October 13, 2015 in Las Vegas, Nevada. Five Democratic presidential candidates are participating in the party's first presidential debate. (Photo by Joe Raedle/Getty Images)

Three notable factual errors from the Democratic debate

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Checking a claim that 'nobody did anything wrong' on Benghazi

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Republican presidential hopeful Carly Fiorina looks on during the Republican presidential debate at the Ronald Reagan Presidential Library in Simi Valley, California, on September 16, 2015.

Carly Fiorina's claims on an anti-abortion video

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What Jeb Bush, Trump and Warren all agree on: Taxes

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Democratic presidential candidate and former U.S. Secretary of State Hillary Clinton speaks to guests gathered for a campaign event on the campus of Des Moines Area Community College on August 26, 2015 in Ankeny, Iowa.

Fact-checking a Hillary Clinton email claim

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