## Facts

- Rodrigo Partida, a Mexican-American defendant, was indicted by a Hidalgo County, Texas grand jury and convicted of burglary in state court.
- Partida challenged his conviction, alleging the county’s grand jury selection process intentionally discriminated against Mexican-Americans in violation of the Fourteenth Amendment.
- Texas used a discretionary “key-man” selection system: jury commissioners appointed by a state district judge selected prospective grand jurors, and the judge later tested statutory qualifications.
- Statutory qualifications included Texas and county citizenship, being a qualified voter, literacy, sound mind, good moral character, and no felony conviction or pending indictment/accusation.
- Evidence showed Mexican-Americans were about 79% of the county population, but over an 11-year period only about 39% of those summoned for grand jury service were Mexican-American.
- Mexican-Americans were readily identifiable in the selection process, including through Spanish surnames.
- Partida sought federal habeas relief after exhausting state remedies; the district court denied relief, but the Fifth Circuit reversed and granted relief.

## Issues

1. Whether Partida’s statistical and contextual evidence established a prima facie case of intentional discrimination against Mexican-Americans in grand jury selection.
2. Whether the State rebutted any prima facie showing with competent, race-neutral explanations for the disparity.

## Decision

- The Supreme Court affirmed the court of appeals and held that Partida established a prima facie case of intentional discrimination in grand jury selection.
- The Court concluded the State failed to rebut the resulting presumption with competent evidence.
- The Court rejected reliance on the notion that Mexican-Americans were a “governing majority” in county politics as a sufficient answer to the proof of discrimination in jury selection.
- The Court declined to presume that members of an identifiable group will not discriminate against members of the same group.

## Legal Principles

- A prima facie equal-protection violation in grand jury selection is shown by: (1) membership in a recognizable, distinct class; (2) substantial underrepresentation by comparing population share to those called for service over a significant period; and (3) a selection procedure susceptible to abuse or not racially neutral.
- Once a prima facie case is established, the burden shifts to the State to rebut discriminatory purpose with evidence that the disparity is attributable to race-neutral factors.
- Significant, sustained statistical disparities can support an inference of purposeful discrimination; for large samples, differences exceeding roughly two or three standard deviations make a random-selection explanation suspect absent contrary evidence.
- A discretionary “key-man” selection method may support an inference of discrimination when it allows substantial subjective choice and the affected class is readily identifiable.
- General testimony about how commissioners were appointed and instructed is insufficient rebuttal where the State does not present evidence explaining how statutory qualifications were actually applied to produce the disparity.

## Conclusion

The Court held that sustained, statistically significant underrepresentation of Mexican-Americans under a discretionary grand jury selection system established a prima facie equal-protection violation, and habeas relief was warranted because the State did not provide competent evidence showing the disparity resulted from race-neutral causes.


Castaneda v. Partida, 430 U.S. 482 (1977)