SIOUX FALLS - A Republican activist thought to be behind a controversial series of political robo-calls has been added as a defendant in a Minnehaha County lawsuit.

The Argus Leader reports that 31-year-old Daniel Willard will be forced to testify under oath in the case through a deposition.

Willard has been charged criminally in Lake County in connection with two of the calls.

The Rushmore Political Action Committee and Dan Lederman initially filed the lawsuit against 100 unnamed defendants and Veterans Against Unethical Politicians and Republican Values Voters.

Joel Arends, Lederman's attorney, says Willard will have to reveal who was funding the calls.

Willard's lawyer, R. Shawn Tornow, says some of the information sought by the plaintiffs' attorneys is too broad and "they're engaged in an unproductive fishing expedition."

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