Six South Dakota couples have filed a federal lawsuit challenging South Dakota's ban on same-sex marriage, leaving only North Dakota without such an action.
The federal complaint filed Thursday in Sioux Falls challenges a law and voter-approved constitutional amendment.
Attorney General Marty Jackley has said he's obligated by law to defend the ban.
He's among the defendants that also include Gov. Dennis Daugaard, Health Secretary Doneen Hollingsworth, Public Safety Secretary Trevor Jones, Pennington County Register of Deeds Donna Mayer and Brown County Register of Deeds Carol Sherman.
The couples are Jennie and Nancy Rosenbrahn and Jeremy Coller and Clay Schweitzer, of Rapid City; Lynn and Monica Serling-Swank, of Brandon; Krystal Cosby and Kaitlynn Hoerner and Barbara and Ashley Wright, of Aberdeen; and Greg Kniffen and Mark Church, of Sioux Falls.