By Brendan O'Brien
MILWAUKEE (Reuters) - A conservative organization in Wisconsin filed a federal lawsuit against several public officials on Monday, saying its members' civil rights were violated during an ongoing secret probe into campaign financing, court documents showed.
The Wisconsin Club for Growth filed the lawsuit in the U.S. District Court for the Eastern District of Wisconsin, accusing investigators of violating its members' freedom of speech, association and equal protection rights.
The organization is asking the court to halt the 17-month probe into what The Wall Street Journal has described as claims of illegal coordination between special interest groups and political campaigns.
In the complaint, the group contends that investigators have infringed on its members' civil rights by sidelining them from political activities during the 2014 election cycle, including Republican Governor Scott Walker's re-election campaign.
The group has been targeted for alleged unlawful "coordination" with Walker's campaign for fiscal reforms, David Rivkin, a lawyer for the Wisconsin Club for Growth and its director Eric O'Keefe said in a statement released on January 15.
In its complaint filed on Monday, the group described the nature of the probe as an investigation into the involvement of about 30 social welfare organizations in connection with 13 recall elections in 2011 and 2012.
Democrats, angered by collective bargaining reforms passed by Republican lawmakers in 2011, successfully gathered enough signatures on petitions to force Walker to defend his seat in a special election in 2012.
Armed with a massive fundraising effort spurred by conservatives inside and outside of the state of Wisconsin, Walker won.
The group contends the current investigation and an earlier secret probe were politically driven, noting that both were initiated by Milwaukee County District Attorney John Chisholm, a Democrat.
In addition to Chisholm, the defendants include a special prosecutor, two assistant Milwaukee County District Attorneys, an investigator and a judge.
"This secret investigation and gag order on conservative activists is intended to stop their political successes in Wisconsin," O'Keefe said in a statement on Monday.
Chisholm could not be reached immediately for comment.
In Wisconsin, secret "John Doe" investigations allow prosecutors legal room to call witnesses, request search warrants and offer immunity without probable cause that a crime has been committed.
A gag order is in place, prohibiting witnesses and lawyers from talking about the secret probe. Lines were also blacked out throughout the complaint filed by the Wisconsin Club for Growth and other court documents remain under seal.
The current investigation is the second such probe which Chisholm has aimed at conservatives in the last four years. The first investigation began in May 2010 and resulted in charges filed against six people, including four of Walker's aides.
A Wisconsin appeals court in January denied a request to end the current secret probe, but allowed a number of court documents to be unsealed.
(Reporting by Brendan O'Brien; editing by Cynthia Johnston, Mohammad Zargham and G Crosse)