David Alexander Clarke Jr. (born August 21, 1956) is an American former law enforcement official who served as Sheriff of Milwaukee County, Wisconsin, from 2002 to 2017.

In 2002, Clarke was appointed to the position by Republican governor Scott McCallum and later elected that same year to his first four-year term. He was reelected in November 2006, 2010 and 2014. Although Clarke declared himself as a Democrat after his appointment as sheriff and ran as a Democrat in a heavily Democratic county, many of Clarke's political views align with those of conservative Republicans; he refused to join the Wisconsin Democratic Party, instead promoting conservative views, and allying himself with Republican officials.

As sheriff, Clarke frequently clashed with other Milwaukee County officials over the budget and other matters, and came under scrutiny for deaths and alleged mistreatment of jail inmates. One man died of thirst in what a coroner ruled was a homicide, and pregnant women were handcuffed and shackled while undergoing labor. Clarke frequently appeared as a guest on Fox News through February 2018 and was a speaker at the 2016 Republican National Convention. He resigned as sheriff in August 2017. A vocal supporter of President Donald Trump, Clarke garnered attention for controversial and sometimes inflammatory social-media posts, and was considered for a role in the Trump administration. After resigning as sheriff, Clarke joined the pro-Trump super PAC America First Action as a spokesman and senior advisor; he left the group in 2019.

Early life, education, and early career Clarke was born in Milwaukee, one of five children of Jeri and David Clarke Sr.Kurt Chandler, The New Black Power, Milwaukee Magazine (July 25, 2003). His father was a paratrooper with the 2nd Ranger Infantry Company. His uncle was NFL player Frank Clarke, whom he idolized.

Clarke Jr. attended Marquette University High School where he played for the varsity basketball team. After finishing high school, Clarke took classes at the University of Wisconsin in Milwaukee but dropped out during his first year when he got a job driving beer trucks.

His career in law enforcement began in 1978 at the Milwaukee Police Department (MPD). He "rose through the ranks at a slow but steady pace in his 24 years with the department". Clarke was a patrol officer for eleven years and then a homicide detective; he was promoted to lieutenant of detectives in 1993 and captain in 1999.

Clarke's career was not without controversy; in 1994, the mother of a 15-year-old boy filed a complaint alleging that Clarke used excessive force when arresting her son. According to public documents, Clarke was returning from a vacation when he spotted five teenagers heaving rocks at passing cars. Clarke chased down the teens, drew his service revolver and ordered them to lie on the ground. He admitted to using his foot to turn one boy over as he searched for weapons. The boy's mother claimed Clarke put a gun to her son's head and kicked him in the side, causing bruised ribs that required medical attention. However, the Fire and Police Commission ruled there was insufficient evidence to charge Clarke and dismissed the case.

In 1999, Clarke received a B.A. in Management of Criminal Justice from Concordia University Wisconsin's School of Adult and Continuing Education.Milwaukee Sheriff, CU Alum Receives Award (press release), Concordia University Wisconsin (April 1, 2016). In January 2002, Milwaukee County Sheriff Leverett F. Baldwin resigned midway through his term to take a pension payout. Clarke was one of ten applicants for the position, and Governor Scott McCallum appointed him on March 19, 2002. He was elected to a full term later in 2002, and was reelected in 2006, 2010, and 2014.

Master's thesis plagiarism In 2013, Clarke received a master's degree in security studies from the Naval Postgraduate School (NPS). In May 2017, CNN reported that Clarke had plagiarized portions of the thesis he completed as part of the requirements for this degree, stating that in the thesis, "Clarke failed to properly attribute his sources at least 47 times." The thesis ("Making U.S. security and privacy rights compatible") was found to have lifted material verbatim from several sources without proper citation, including reports by the American Civil Liberties Union, the 9/11 Commission Report, and George W. Bush's memoir Decision Points. Clarke provided footnotes to sources that he used, but did not properly place quotations around verbatim words of his sources, which is an act of plagiarism according to the NPS. Following the report, the NPS removed the thesis from its online archive.John Fauber, Report: Sheriff David Clarke plagiarized parts of homeland security thesis, Milwaukee Journal Sentinel (May 21, 2017): "the Naval Postgraduate School removed Clarke's thesis from its website and replaced it with the following note: 'This item was removed from view at the discretion of the Naval Postgraduate School.'" In response to the report, Clarke called journalist Andrew Kaczynski, who broke the story, a "sleaze bag" and denied that he had plagiarized.

In a July 2017 letter to Clarke, NPS dean of students, Commander Paul Rasmussen, wrote that he concurred with the Honor Code Board that Clarke's thesis was "in violation" of the school's honor code but that the "violation was not a result of any intentional deception or misappropriation efforts". Rasmussen instructed Clarke to submit a revised thesis within 100 days or NPS would "initiate degree revocation".Chris Massie & Andrew Kaczynski, Former Sheriff David Clarke must revise thesis or risk losing degree, docs reveal, CNN (September 15, 2017). Clarke received several extensions on the original deadline before submitting his revised thesis in March 2018; NPS officials informed Clarke that his edits were satisfactory, and allowed him to retain his degree.

Political views Clarke has "built a following among conservatives with his provocative social media presence and strong support of Donald Trump".Ivan Moreno, Firebrand Milwaukee sheriff takes job with Homeland Security, Associated Press (May 17, 2017). His prominence as a right-wing firebrand has made him a controversial and polarizing figure.Alex Yablon, Trump Taps David Clarke, a Staunch NRA Ally, For Homeland Security Post: The Milwaukee lawman joined the gun group's junket to Russia, while compiling accusations of negligence and abuses of power at home, The Trace (May 17, 2017).Milwaukee sheriff's star rises, but he remains polarizing, Chicago Tribune news services (February 5, 2017).Wesley Lowery & Lisa Rein, Controversial Milwaukee sheriff David Clarke says he’ll be appointed to high-ranking DHS post, but agency has not confirmed, Washington Post (May 17, 2017).

Planned Parenthood He has criticized Planned Parenthood, suggesting instead that it be renamed "Planned Genocide".

Comments on race In 2015, Clarke received criticism for his statement on his podcast: "Let me tell you why blacks sell drugs and involve themselves in criminal behavior instead of a more socially acceptable lifestyle: because they're uneducated, they're lazy and they're morally bankrupt. That's why."

In 2017, Clarke attracted attention and criticism for trading racial insults with Marc Lamont Hill, an African-American CNN commentator; on Twitter, Clarke used a racial slur ("jigaboo") to insult Hill.Alex Griswold, CNN's Marc Lamont Hill, Sheriff David Clarke Fling Racial Slurs at Each Other on Twitter, (January 17, 2017).Theo Keith, Milwaukee County launches investigation of Sheriff Clarke over airplane complaint, Clarke says it's a "witch hunt", WITI (January 25, 2017).D.L. Hughley, David Clarke and Marc Lamont Hill Trade Insults with Each Other, WZAK.

Black Lives Matter Clarke is a frequent and vociferous critic of the Black Lives Matter (BLM) movement, referring to it as "Black Lies Matter" and describing the movement as a hate group.David Clarke, It's time to stand up to Black Lives Matter, Fox News (July 11, 2016).Brendan O'Brien, Black Milwaukee sheriff takes on Black Lives Matter movement, Reuters (February 27, 2016). Clarke denies that police officers are more willing to shoot black suspects than white suspects, has labeled BLM activists "subhuman creeps", and has called for the targeted eradication of the movement "from American society". He has also claimed that Black Lives Matter would eventually join forces with ISIS in order to destroy American society.David Clarke, Before long, Black Lies Matter will join forces with ISIS to being down our legal constituted republic. You heard it first here., Twitter (October 27, 2015). He has urged the Southern Poverty Law Center to include BLM among the hate groups it monitors. Clarke has blamed "liberal policies" for rioting and other issues in American cities. Clarke's stance on the movement has been criticized by the Milwaukee chapter of the NAACP and other activists.

Clarke has harshly criticized various black critics of police abuses. He has called former attorney general Eric Holder an "a[ss]hole" and accused him in testimony before the Senate Judiciary Committee of "outright hostility" toward police, referred to Al Sharpton as a "charlatan" and criticized Beyoncé for her reference to the Black Panthers in her halftime-show performance at the 2016 Super Bowl.

Gun control In January 2013, Clarke was featured on a series of public radio ads that said citizens could no longer rely on the police for timely protection and should arm themselves. Later that month, Clarke appeared on the CNN program Piers Morgan Live, with Milwaukee Mayor Tom Barrett, who "said it was irresponsible of Clarke to 'basically imply' that it won't help citizens to call 911 when they need help".

In 2015, Clarke traveled to Moscow on a $40,000 trip, with all expenses paid by the National Rifle Association of America, Pete Brownell (an NRA board member and CEO of a gun-parts supply company) and "The Right to Bear Arms", a Russian pro-firearms organization, founded by Maria Butina, a Russian national, who pleaded guilty in 2018 to being an unregistered Russian agent. During the meeting, Clarke met the Russian foreign minister and attended a conference at which Russian official Aleksander Torshin, a close ally of Vladimir Putin, spoke.

In 2018, Clarke attracted attention for using Twitter to promote a conspiracy theory about the Stoneman Douglas High School shooting in Parkland, Florida; Clarke tweeted that "The well ORGANIZED effort by Florida school students demanding gun control has GEORGE SOROS' FINGERPRINTS all over it", suggesting that the students from Parkland were being manipulated by Soros to organize for gun control.Daniel Bice, Former Sheriff David Clarke files for divorce in Milwaukee County, Milwaukee Journal Sentinel (February 23, 2018).

Suspension of habeas corpus in the United States Clarke has called for the suspension of habeas corpus in the United States in a December 2015 appearance on his radio program, where he asserted that there were "hundreds of thousands" or "maybe a million" people who "have pledged allegiance or are supporting ISIS, giving aid and comfort", and stated that "our commander in chief ought to utilize Article I, Section 9" to imprison them at the Guantanamo Bay detention camp "and hold them indefinitely under a suspension of habeas corpus".Jeremy Stahl, Potential Homeland Security Pick Wanted to Suspend Habeas Corpus, Jail One Million, Slate (November 29, 2016).Pema Levy, Potential Trump Pick for Homeland Security Wants to Send up to 1 Million People to Gitmo, Mother Jones (November 28, 2016).

Ideology and relationships with Republican and Democratic parties