Immigration activists rally April 23, 2019, outside the Supreme Court as the justices hear arguments over the Trump administration’s plan to ask about citizenship on the 2020 census, in Washington. A new court filing Thursday, May 30 by lawyers opposing adding the citizenship question to the 2020 census alleges a longtime Republican redistricting expert played a key role in making the change. (AP Photo/J. Scott Applewhite, File)