Parliamentary sovereignty, parliamentary supremacy, or legislative supremacy is a concept in constitutional law that applies to some parliamentary emocracies. Under parliamentary sovereignty, a legislative body has absolute sovereignty, meaning it is supreme to all other government institutions (including any executive or judicial bodies as they may exist). Furthermore, it implies that the legislative body may change or repeal any prior legislative acts. Parliamentary sovereignty contrasts with notions of judicial review, where a court may overturn legislation deemed unconstitutional. Specific instances of parliamentary sovereignty exist in the United Kingdom, Israel and New Zealand. As a philosophical and jurisprudential idea, it has problems similar to the omnipotence paradox.