Final answer:
The Supreme Court has protected the civil rights of minority groups by broadening the interpretation of the Fourteenth Amendment and utilizing other legal provisions, as evidenced by decisions from Hernandez v. Texas to Obergefell v. Hodges, which upheld civil rights across ethnic and sexual orientation lines.
Step-by-step explanation:
The timeline of Supreme Court rulings from Hernandez v. Texas in 1954 to Obergefell v. Hodges in 2015 demonstrates how the Supreme Court has protected the civil rights of minority groups through its interpretations of the Fourteenth Amendment and other laws. In Hernandez v. Texas, the Court recognized that the equal protection clause of the Fourteenth Amendment also extends to ethnic groups beyond the traditional binary of white or African American. In Boynton v. Virginia, the Court ruled that discrimination in interstate transportation is unlawful under the Interstate Commerce Act. Finally, in Obergefell v. Hodges, the Court expanded the protection of civil rights to include same-sex marriage under the same equal protection clause, emphasizing that it applies irrespective of sexual orientation.
This demonstrates that the Supreme Court has not limited itself to using only the Fourteenth Amendment but has also relied on other legislative acts to ensure civil rights are upheld, reaffirming that all persons are entitled to equal protection of the laws, which is a fundamental principle of American constitutional democracy.