What principle is established by the 14th Amendment?

The principle established by the 14th Amendment is equal protection under the law. Ratified in 1868, the 14th Amendment was a key part of the Reconstruction Era amendments aimed at securing rights for formerly enslaved individuals. Its Equal Protection Clause mandates that no state shall deny any person within its jurisdiction the equal protection of the laws. This means that individuals in similar circumstances must be treated equally by the law, which has formed the foundation for various civil rights advancements, addressing issues of discrimination and ensuring fairness in legal proceedings.

The other options relate to different historical contexts and amendments. Women’s suffrage relates to the right to vote for women, which was secured through the 19th Amendment. Prohibition of alcohol was enacted through the 18th Amendment and later repealed by the 21st Amendment. Income tax authorization involves the 16th Amendment, which allows Congress to levy an income tax. Each of these topics represents significant developments in American legal history but does not pertain to the core principle of equality established by the 14th Amendment.