How has the US Supreme Court interpreted the equal protection clause in voting rights?

The court has entered the 'political thicket' (Colegrove v. Green (1946) 328 U.S. 549, 556, 66 S.Ct. 1198, 90 L.Ed. 1432) to enforce the equal protection clause in three principal contexts. The first such category is composed of cases involving state laws that exclude various groups from voting in all or in certain types of elections. The court has eliminated many of these barriers to the electoral process; it has invalidated residency requirements excluding servicemen, ²⁰ qualifying examinations excluding racial minorities, ²¹ poll taxes excluding the poor and indigent, ²² and property qualifications excluding the landless. ²³ The effect of these, and of related decisions, ²⁴ has been to expand sharply the number of persons entitled to participate actively in the election process. This court, for example, complying with principles established by the above line of cases, has limited the application of two voter qualification provisions contained in our state Constitution. ²⁵

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