Judicial Policymaking
We must remember that the Supreme Court’s job is to look at the laws and the cases in front of them and compare them with the Constitution. If the laws or a prior decision in a case is unconstitutional, it is the Supreme Court's job to find them so. What many see as the Supreme Court making laws is really the Supreme Court setting precedent. This action of taking into account a higher court’s (or another court’s) rulings and ruling similarly has been common in all courts that stem from the English court system model – we can see similar occurrences in British, Canadian, and Austrian courts as well as our own. The Supreme Court of the United States’ job is not to enforce laws or their rulings overall. The Supreme Court’s job is to set legal standards of law while enforcement falls into the jurisdiction of the executive branch and through the executive branch the various law enforcement agencies and the lower courts follow precedent.
On the subject of justices serving for a lifetime and having political alignments when they are appointed it is imperative for us to remember the principles behind setting Supreme Court justices' terms for a lifetime and not within the grasp of the executive branch to remove them. The delegates at the constitutional convention wanted the Supreme Court justices to be free of “momentary passions of the people”, to make rulings on the case law that applies to each individual case, be free from political pressure, be free of the fear that they will not be reelected if they rule this way or that, and free of the fear that if they rule against the president’s wishes he or she will remove them and appoint someone who shares the president’s views.
Consider how a judge who is elected into office of any kind (from the lowest city court on up) acts in terms of how often they follow their party preference on individual cases and we will see that quite often they will rule in a way that pacifies their party members or the party with the most clout. With that in mind look at how appointed judges act in the same situations, they pay little or no mind to the opinion of the prevailing political party and attempt to rule on the cases before them unbiased and according to the case law. Of course, judges and justices are people to and have their own opinions and values; and possibly at the beginning of their tenure they will seem to rule more in line with their personal beliefs and that of the party that appointed or enabled their election, but over time they tend to “grow their own brain” and move away from personal feelings and political pressure and move closer to case law. That is why lifetime appointments to judgeships or justiceships are so important and seem to be the best option. They tend to be substantially less tainted than elected judges or members of Congress.