An "equality principle" is a philosophical, moral, and legal doctrine asserting that all human beings are "equal," and that they ought to be treated "equally" under the law. The doctrine leaves two very important unanswered questions:
- In what respect are people "equal?"
- How ought people to be treated equally under the law?
Equality of Worth and Rights
The Declaration of Independence provides that "We hold these truths to be self-evident, that all men are created equal, that they are endowed, by their Creator, with certain unalienable Rights, that among these are Life, Liberty, and the pursuit of Happiness."
U.S. President Abraham Lincoln later reaffirmed the importance of this concept of equality "Four score and seven years ago our fathers brought forth on this continent, a new nation, conceived in liberty, and dedicated to the proposition that all men are created equal."
These statements stand in stark contrast to the view, commonly held at the time, that certain people (e.g. kings, aristocrats, whites) were of inherently higher value than others, and were entitled to more rights, simply by virtue of the circumstances of their birth.
How ought people to be treated equally under the law?
Equality of Treatment
According to this view, similarly situated people should be treated equally. For instance, all people who commit the same crime under the same circumstances should be punished in the same way; differences in treatment should arise only from differences in the circumstances surrounding the crime.
This concept leaves unanswered two important question: First, similar in which respects? If one man is beaten as a child and then beats his children, and another man is raised by great parents and beats his children, should we consider the men's different backgrounds in deciding how to treat them under the law? Which circumstances are relevant in determining which people are "similarly situated?" Second, how much should different circumstances affect our treatment? How much of a difference should the men's differing backgrounds make?
Justice Stevens, writing for the Supreme Court, included dictum supporting an equality principle for gender in Miller v. Albright, 523 U.S. 420,).
Equality of Opportunity
Under this view, advanced by people such as Rawls and Dworkin, individuals should be given equal opportunity to succeed -- thus, society is obliged to equalize differences in opportunities -- for instance, social position, family wealth, innate intelligence, etc. Inequalities are only justified by factors within an individual's control, such as individual work ethic, hours worked, etc.
Equality of Welfare
Under this view, advanced by people such as Marx, individuals should be given an equal degree of welfare. "From each according to his abilities; to each according to his needs." Thus those with great abilities and few needs are obliged to support those with few abilities and great needs.
Equality principle in US Law
An "equality principle" is judge-made doctrine that seeks equal treatment on the basis of criteria that can range from conditions for admitting states to the Union, taxation, race or gender. Liberals champion an equality principle for race and gender even though though Congress has repeatedly reject results-oriented rules, such as quotas.
Justice Stevens, writing for the Supreme Court, included dictum supporting an equality principle for gender in Miller v. Albright, 523 U.S. 420, 442 (1998).