The equal protection clause of the 14th Amendment to the U.S. Constitution does not protect against discrimination on the basis of gender or sexual orientation, according to Supreme Court Justice Antonin Scalia.
For the record, the 14th Amendment's equal protection clause states: "No State shall make or enforce any law which shall abridge the privileges or immunities of citizens of the United States; nor shall any State deprive any person of life, liberty, or property, without due process of law; nor deny to any person within its jurisdiction the equal protection of the laws."