ABERDEEN, S.D. (AP) — A federal judge has struck down South Dakota's ban on out-of-state money for ballot question campaigns.

U.S. District Judge Charles Kornmann on Thursday ruled unconstitutional the ballot question approved by South Dakota voters last November.

Kornmann says the measure violates First Amendment political speech rights and also violates the Commerce Clause by interfering with interstate transfer of money to ballot question campaigns in South Dakota.

The law is scheduled to take effect July 1, but the judge blocked state officials from enforcing the law.

Former House Speaker Mark Mickelson sponsored the initiative. He said it was necessary to preserve the ballot measure process for state residents.

The South Dakota Newspaper Association, South Dakota Retailers Association and South Dakota Broadcasters Association were among those challenging the measure. The state can appeal.

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