A judge who is elected may still be subject to outside influence and potentially corrupting influences. However, there is less likely to be a single person or entity (as in the case of an appointed judge) that the judge may feel that he owes loyalty to and who can exert strong pressure or influence on the judge. This independence allows the judge to feel more secure and independent in the decisions he makes, reducing likelihood of corruption.
Elections can breed corruption, because people running for
office need funds to run their campaigns. They may pander to moneyed interests,
and may also take popular positions on courtroom issues, rather than
principled ones. The Justices of the Supreme Court serve for life, so that they
will be above partisan politics, and spared the need to serve anything but their
principles. All judges should be appointed, so they too will be impartial.