By Hans von Spakovsky, ACRU Policy Board member, in SCOTUSblog

Evenwel v. Abbott may wind up being the most important voting case in sixty years. Its political ramifications could rival those of Reynolds v. Sims, the 1964 case that established the principle of “one person, one vote” under the Equal Protection Clause of the Fourteenth Amendment. The key question in Evenwel is what population does that principle require legislatures to use when they are redrawing legislative districts?

Prior to Reynolds, states like Alabama and Tennessee had refused to redistrict for more than half a century, despite a dramatic, nationwide population shift from rural to urban areas. These state legislatures were dominated by rural legislators, who were not willing to reapportion and lose their power and control.

Under the principle established in Reynolds, districts have to be drawn “on a basis that will insure, as far as is practicable, that equal numbers of voters can vote for proportionally equal numbers of officials.” Within two years of the Reynolds decision, legislative districts had been redrawn in almost every state, and urban areas gained a substantial number of legislative seats.

Today, lawmakers from urban areas dominate many state legislatures because of the huge influx of non-citizens, both legal and illegal, into predominantly urban settings. This greatly increases the population of non-voters who can be and are used to fill in urban legislative districts. If the Court rules for the plaintiffs, there could be a similar loss of clout by urban areas that rural districts experienced after Reynolds.

In this case, Sue Evenwel and Edward Pfenninger are contesting the state senate districts drawn by the Texas legislature in 2013. The legislature used total population in determining whether the population of each senate district met equal protection requirements. Evenwel, a registered voter in Senate District 1, and Pfenninger, a registered voter in Senate District 4, filed suit because both the number of citizens of voting age and the number of registered voters in these two districts deviate substantially – between thirty-one and forty-nine percent – from the “ideal” population of a Texas senate district.

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