Ideology: Fair game since 1795
"Conservatives Senators are tripping over themselves to claim ideology is off limits in questioning a Supreme Court nominee. History shows thatÃ¢â‚¬â„¢s not true," writes Ian Millhiser. "In 1795, President George Washington nominated Justice John Rutledge to be Chief Justice of the United States. Rutledge, a former Associate Justice of the U.S. Supreme Court and current Chief Justice of South Carolina, was 'well qualifed' by any standard, but Senate partisans blocked his nomination for one simple reason: ideology. Justice Rutledge opposed the Jay Treaty, a hot button issue in 1795.
Unlike President Bush, President Washington respected the right of the Senate to reject judicial nominations. In 1789, Washington had even explained just how free the Senate was to do so: 'Just as the President has a right to nominate without assigning reasons, so has the Senate a right to dissent without giving theirs.'" (Think Progress)