The case is Janis v. Nelson (D. S.D.). The court recently denied summary judgment in favor of the state. Here are some of the materials so far:

Janis v Nelson DCT Order on Motion for Summary J

Janis v Nelson DCT Order on Motion for Protective Order

An excerpt from the summary judgment order:

In summary, plaintiffs allege that their names were unlawfully removed from the statewide and county voter registration rolls after having been sentenced to probation for their felony convictions and that they were not given the opportunity to cast provisional ballots despite the existence of both federal and state laws authorizing the use of provisional ballots if a question exists about voter eligibility. Plaintiffs also allege that their voting rights under Section 2 of the Voting Rights Act have been denied because defendants’ actions have a disparate and negative impact on Native Americans and that Section 5 of the Voting Rights Act is being violated because defendants’ actions constitute a change in voting practices and procedures that has not been precleared. Plaintiffs seek declaratory, injunctive, monetary, and other forms of relief.