Smith v. Allwright
The Democratic Party of Texas required all voters to be white as part of state law. Black Houston dentist Lonnie E. Smith sued a Texas county election official for being denied the right to vote in the primary election. Then-lawyer Thurgood Marshall argued to the Supreme Court that Texan Democrats were keeping Black people from voting in the primary, violating their 15th and 14th Amendment rights. The outcome resulted in the overruling of the 9-year-old Grovey v. Townsend case which initially allowed Texas to place race-based restrictions on voting. Following Smith, the number of Black voters in the South rose by 100,000, totaling to one million by 1952.