The American Civil Liberties Union is challenging a new law signed by South Dakota Gov. Kristi Noem aimed at potential protests against the planned Keystone XL oil pipeline.
The ACLU filed a federal lawsuit Thursday on behalf of groups and individuals planning to protest the pipeline or encourage others to do so.
Noem signed the act on Wednesday that allows officials to pursue money from demonstrators who encourage violence. The Republican governor also signed another bill requiring pipeline companies to help pay extraordinary expenses such as the cost of policing during protests, but the ACLU is not challenging that new law.
The pro-pipeline GAIN Coalition says the legislation provides "clarity about what crosses the line."
But the ACLU and American Indian tribes say Noem's approach will stifle free speech.