Within its nearly three-page entry on the U.S. Supreme Court, the American Conservatism encyclopedia offers a good synopsis of the reason why conservatives often shake their heads as they read high court rulings:

The role of courts from time immemorial until the 1950s was that of deciding particular cases so as to vindicate settled rights in light of specific circumstances. Today, however, the Supreme Court, not to mention lower courts, engages in wholesale rearrangement of political, social, and even religious institutions (e.g., marriage) to meet judges’ subjective views of what is right. This transformation has undermined self-government. The Court has usurped for itself the right to define what a right is. Moreover, it has concentrated power in itself, first as the sole arbiter of the Constitution’s meaning (thus freeing it from the trouble of justifying its textual contortions), and second, as the sole branch able to exercise judicial, legislative, and executive functions. Concentration of all three of these powers in one branch of government was defined by the founders as the very definition of tyranny.