Leif Gustav Willy Persson - better known as Leif GW Persson - is a Swedish criminologist and novelist. He was a professor in criminology at the Swedish National Police Board from 1992 to 2008. He is known for his crime fiction novels and for his regular appearances as an expert commentator on notable crime cases in television and newspapers. Between 1999 and 2009 he participated as an expert commentator on the television show Efterlyst (Swedish TV program, equivalent of America's Most Wanted) on TV3. Since 2010, he is the expert commentator of Veckans Brott - roughly translated into Weekly Crimes or Crimes of the Week - on SVT.