A man was forcibly removed from an overbooked United Airlines flight travelling from Chicago to Louisville on April 9, sparking outrage after videos of the incident were posted on social media.

Social media went up in flames when a video was posted of a man being dragged off an overbooked United Airlines flight after refusing to give up his seat.

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It turns out that man is Dr. David Dao. There’s no evidence the events in Dao’s past in any way influenced how he was treated on the airplane earlier this week.

Dao, 69, began pursuing his medical degree from the University of Medicine at Saigon University in Ho Chi Min City, Vietnam, graduating in 1974. Dao was licensed in Kentucky with a specialty in pulmonary disease.

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Dao worked at Hardin Memorial Hospital and as a medical practitioner at a prison in Michigan City before opening up a practice with his wife, according to reports from Heavy.com. Since then however, Dao has found himself in some hot water with the law.

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According to records from the Kentucky Board of Medical Licensure, Dao was indicted for drug-related offences in October 2003, including charges of trafficking in a controlled substance, obtaining drugs by fraud and deceit, unauthorized prescribing and dispensing or administering of controlled substances.

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In 2003, Dao was charged with 98 counts of illegally prescribing and trafficking painkillers, including hydrocodone, OxyContin and Percocet. He was a co-defendant in the case along with Brian D. Case, who was indicted with 33 drug-related charges. Dao was then convicted in 2004, and was placed under five years of supervised probation.

While the Kentucky Board of Medical Legislature was investigating these criminal charges, it reportedly learned that Dao had sexually pursued a male patient. This included performing unnecessary physical examinations, continually prescribing him hydrocodone, and eventually hiring him on as his office manager.

Shortly after, the man allegedly left his job because of the continual sexual comments and advances made by Dao. In a criminal complaint filed by the employee, the complainant says that Dao “pursued him aggressively” and arranged to provide him with prescription drugs in exchange for sex.

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Because of his transgressions, his medical licence was eventually suspended by the Kentucky Board of Medical Legislature in 2003. He applied to have it reinstated in 2007 but the application was denied. However, after applying several times, completing several workshops and undergoing many psychological evaluations, board chair C. William Briscoe allowed Dao to continue practising medicine in the state of Kentucky in 2016.

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In addition, Dao is an avid and successful poker player, who has apparently made $243,644 in multiple World Series of Poker tournaments. According to his WSOP profile, Dao began playing in 2006, with his biggest win coming in 2009 at $117,774. At this time, his medical licence was still suspended. According to a document from the Sullivan University Herald, Dao also “took a sabbatical from his medical practice,” to take cooking classes.

Regardless of the information surfacing about Dao’s past, airport officials told the Associated Press that Dao’s multifaceted history had nothing to do with how he was removed from the flight. United Airlines CEO Oscar Munoz recently issued an apology for the events that took place, stating that “no one should ever be mistreated this way.”

— With files from The Associated Press

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