Legal certainty (German: Rechtssicherheit; Indonesian: kepastian hukum) is the principle that the law should be clear, accessible, stable and applied consistently, so that those subject to it can understand their rights and duties and foresee the legal consequences of their actions.
Elements
Legal certainty requires that laws be published and comprehensible, that they apply prospectively rather than retroactively, that they are not changed so frequently as to defeat reasonable planning, that officials apply them consistently, and that final decisions of courts and authorities are respected and enforced.
A Classic Tension
The German legal philosopher Gustav Radbruch described law as serving three values: justice, purposiveness (expediency) and legal certainty. These may conflict. Radbruch's formula holds that positive law should generally prevail even when unjust, unless the injustice is so intolerable that the law must yield to justice.
In Indonesia
Article 28D(1) of the 1945 Constitution guarantees every person the right to recognition, guarantees, protection and fair legal certainty, and to equal treatment before the law. The principle is frequently invoked before the Constitutional Court against vague or contradictory provisions, and it appears among the general principles of good governance in Law No. 30 of 2014 on Government Administration.
For Business
Investors repeatedly identify legal certainty as a decisive factor in deciding where to invest. Predictable licensing, consistent enforcement of contracts and stable tax and regulatory regimes reduce risk and the cost of capital.