The Equal Rights Amendment passed both houses of congress in 1972. However, the amendment was not ratified in enough states to become adopted into the federal constitution. The fact that no such amendment has been passed since is astonishing and an embarrassment. We need an amendment protecting people from discrimination based on sex and also consider a component for preventing discrimination based on gender as well, if we wish to be a forward thinking society.
Text from the original ERA, with the addition of gender:
Section 1. Equality of rights under the law shall not be denied or abridged by the United States or by any State on account of sex or gender.
Section 2. The Congress shall have the power to enforce, by appropriate legislation, the the provisions of this article.