By Mark Potok, Southern Poverty Law Center Senior Fellow It happened again this week. A woman in Louisiana told police that she had been set afire in a horrifying hate crime Sunday — only to have police, after a full-tilt investigation,say yesterday that she had fabricated the story.Sharmeka Moffit, 20, set herself on fire in a park in Winnsboro, LA, Police Chief Lester Thomas told a news conference late yesterday. She earlier told police that she had been attacked by three men of unknown race who were wearing “T-shirt hoodies.” A racial slur and the letters “KKK” were found daubed on her car when police arrived within one minute of her call to 911. A major investigation involving the Winnsboro Police Department, the Franklin Parish Sheriff’s Office and the state police was launched.