In 2013 the Arkansas legislature passed a bill requiring voters at the polls to show a government photo-ID. On April 24, a Circuit Court in Pulaski County ruled that the legislature exceeded its authority, because the bill conflicts with very detailed provisions of the Arkansas Constitution on voter registration and voting. Here is the 8-page opinion. The case is Pulaski County Election Commission v Arkansas State Board of Election Commissioners. The Arkansas Republican Party had intervened in the case on the side of the state. Thanks to Rick Hasen for the link.