Some have called on the President and the Senate Republicans to compromise on the replacement for Justice Antonin Scalia: The President should nominate a “moderate” candidate whom the Senate would then confirm. But any such compromise is likely a bad deal for Republicans. In modern times justices have tended to drift left, unless they were anchored in the conservative legal movement or were already on the left. Ideological ratings of justice year by year show overwhelming evidence of leftward movement. Thus, a moderate today would very likely become at least moderately liberal over time.
There are two reasons for this leftward drift. First, the current of the bar runs left. Thus, justices are surrounded by a dominant legal culture that pulls in one direction. This is not the first time that such a strong current has frustrated one side of the political spectrum. Despite their 24-year control of the Presidency, Jeffersonian-Republicans were unable to change the course of the Federalist Supreme Court. After nineteen straight years of Democratic-Republican Presidents, the Court even upheld unanimously the constitutionality of the Bank of the United States—the bête noire of Thomas Jefferson.
Second, the accolades of our elites go to justices on the left.