Gill v. Whitford, 585 U.S. ___ (2018), was a United States Supreme Court case involving the constitutionality of partisan gerrymandering. Other forms of gerrymandering based on racial or ethnic grounds have been deemed unconstitutional, and while the Supreme Court has identified that extreme partisan gerrymandering can also be unconstitutional, the Court has not agreed on how this can be defined, leaving the question to lower courts to decide.