The State of Texas (defendant) drew its legislative districts based on total population to ensure that each district contained the same number of people. Sue Evenwel and Edward Pfenninger (plaintiffs) each lived in a Texas congressional district that had proportionally high numbers of people that were eligible and registered to vote. Evenwel and Pfenninger challenged the constitutionality of Texas’s districting practice in the United States District Court for the Western District of Texas. Evenwel and Pfenninger argued that Texas’s districting based on total population as opposed to the voter-eligible population diluted their votes in violation of the Equal Protection Clause. The district court dismissed the suit for failure to state a claim, and the United States Supreme Court noted probable jurisdiction.