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Expert Brief

The Impact of Evenwel: How Using Voters Instead of People Would Dramatically Change Redistricting

Using eligible voters rather than total people when drawing legislative districts would make every state legislative map in the country presumptively unconstitutional, requiring them to be redrawn.

Published: December 7, 2015

[View this analysis as a PDF]

A big upheaval could be coming for Amer­ica’s state legis­latures. On Decem­ber 8, the Supreme Court will hear oral argu­ment in Even­wel v. Abbott, a closely watched case from Texas that will decide whether states must change the way they draw legis­lat­ive districts. The new analysis in this paper shows that if the Even­wel chal­lengers prevail, the nation­wide impact will be far greater than previ­ously assumed.

Like other states, Texas currently draws districts so they contain a roughly equal number of people rather than voters. Indeed, over the course of Amer­ican history districts have over­whelm­ingly been drawn this way. But the Even­wel chal­lengers say Texas’s legis­lat­ive plans are uncon­sti­tu­tional because while districts may contain approx­im­ately the same number of people, many vary widely in the number of eligible voters.

So far, a lot of the atten­tion around the case has focused on how chan­ging the way districts are drawn would impact fast-grow­ing Latino communit­ies in certain states. And to be sure, some of the biggest changes would be in boom­ing metro areas, such as Dallas, Hous­ton, and Los Angeles, which have high numbers of both chil­dren and non-citizen immig­rants. Latino major­ity districts, in partic­u­lar, would become much harder to draw in many parts of the coun­try.

But this new Bren­nan Center analysis shows the impact of a change would be far greater than expec­ted and not confined to just a few states. In fact, if the Even­wel plaintiffs win and the rules are changed so lines must be drawn based on citizen voting age popu­la­tion instead of total popu­la­tion:

  • Every state legis­lat­ive map in the coun­try would become presumptively uncon­sti­tu­tional under Equal Protec­tion prin­ciples and would need to be redrawn.
  • Nation­wide, 21.3 percent of state house seats and 16.7 percent of state senate seats would be presumptively uncon­sti­tu­tional. In eight states, the percent­age of house or senate districts with consti­tu­tional prob­lems would be more than 40 percent.
  • Redraw­ing maps to comply with consti­tu­tional require­ments would require chan­ging far more districts because of cascade effects from changes else­where on the map. 

Read the full analysis here and below.

The Impact of Even­wel: How Using Voters Instead of People Would Dramat­ic­ally Change Redis­trict­ing