The second Ku Klux Klan collapsed partly as a result of the backlash against their actions and partly as a result of a scandal involving David Stephenson (at the time a member of the Republican Party, after previous active membership in the Socialist Party and then in the Democratic Party), the Grand Dragon of Indiana and fourteen other states, who was convicted of the rape and murder of Madge Oberholtzer in a sensational trial (she was bitten so many times that one man who saw her described her condition as having been "chewed by a cannibal").
Source
wikipedia