This article reflects on the Equality, as ethical principle to be observed in the political community, in the liberal equality theories developed by the political philosophy of John Rawls, Ronald Dworkin and Amartya Sen, authors of "A Theory of Justice", "The Sovereign Virtue" and "Inequality Re-examined". The works are analyzed through the prism of what unites them, which is the equality as essential element for achieving justice, being our goal to reflect the ethics of this ideal in liberal political views. In this study there is also a consideration about the importance of the topic for the philosophy of law.