In the Carrington v. Rash et al., 1964 case, the U.S Supreme Court ruled that a Texas law which prohibited servicemen from voting in state elections if they moved to Texas during their military service was unconstitutional. The court held that this violated the Equal Protection Clause of the Fourteenth Amendment as it created an arbitrary and unjustifiable distinction between civilian and military residents. The decision emphasized that states cannot deny citizens who move there for any reason, including military service, equal protection under its laws or discriminate against them based on their occupation or manner of entry into the state. This ruling affirmed servicemembers' right to vote wherever they are stationed without discrimination.

In the dissenting opinion for Carrington v. Rash et al., Justice Harlan disagreed with the majority's view that Texas' law barring servicemen from voting was unconstitutional. He argued that states should have a right to determine their own residency requirements for voting, as long as they do not discriminate against any particular group or violate other constitutional rights. In his view, Texas had legitimate reasons to exclude military personnel from voting since they were often transient and might not have strong ties to local communities or issues. Furthermore, he pointed out that many other states had similar laws at the time and believed it was inappropriate for the court to interfere in this matter of state sovereignty without clear evidence of discrimination or injustice.