US District Judge Charles Kornman has ruled IM-24, passed by South Dakota voters last November is unconstitutional.
The measure would have banned out of state contributions to ballot question campaigns.
Former Attorney General Marty Jackley led the legal challenge.
Jackley says the challenge was brought by a coalition of business and media interests.
Jackley says the next step will be up to the Attorney General.
The Attorney General’s office issued a statement: “We respect the decision of the Court. We are reading the decision and are examining the avenues available to our office that best coincide with protecting the best interests of the people and the State of South Dakota.”
(WNAX)