Ronald Reagan told the story of a benefit stealing "welfare queen" back in 1976 to argue for smaller, leaner government. Liberals have complained about the generalization ever since. Paul Krugman called it a "bogus story" as recently as 2007.
It turns out there was a real welfare queen, and that name was given to her by the Chicago Tribune, not Ronald Reagan. According to an excellent piece by Josh Levin for Slate, stealing welfare under false names may have been the least of her crimes:
When I set out in search of Linda Taylor, I hoped to find the real story of the woman who played such an outsize role in American politics—who she was, where she came from, and what her life was like before and after she became the national symbol of unearned prosperity. What I found was a woman who destroyed lives, someone far more depraved than even Ronald Reagan could have imagined. In the 1970s alone, Taylor was investigated for homicide, kidnapping, and baby trafficking. The detective who tried desperately to put her away believes she’s responsible for one of Chicago’s most legendary crimes, one that remains unsolved to this day. Welfare fraud was likely the least of the welfare queen’s offenses.