A free society is based on the idea that each individual should be free from discretionary power and the arbitrary decision-making of others. No one should be "above the law"-—not even members of government. The rule of law means equality under the law, i.e., general, predictable laws enforced equally on all members of society irrespective of social status, sex, race.
"Stripped of all technicalities, [the Rule of Law] means that government in all its actions is bound by rules fixed and announced beforehand-rules which make it possible to foresee with fair certainty how the authority will use its coercive powers in a given circumstance and to plan one's individual affairs on the basis of this knowledge." — F. A. Hayek The Road to Serfdom