The United States is supposed to be governed by laws, not people. However, the Supreme Court is heavily influenced by the personal convictions of its justices. Should the Court allow partisanship to influence the judiciary?
The law is based on fact,precedence, and stare decisis. Opinions and partisanship have absolutely nothing to do with it. Believe me, this is a good thing, otherwise the judge could rule against you if he didn't like the color of your socks. When any case is tried, previous similar cases are examined to see what the ruling was in those previous cases. This is one reason (only one), that the criminal justice system moves so slowly. Do judges bring preformed notions to the bench? Of course they do, they are human, but they can not let personal beliefs or prejudices interfere with the administration of justice.
While I agree with the first answer that the law is "vague" I disagree with the idea that "the most difficult questions of law are about belief."
What a judge really does is interpret the law according to how it has been interpreted before. When a judge in the court of appeals, for example, writes an opinion, everything in that opinion must be backed up and referenced according to "case law." This means that every single idea is compared directly to another case that has been decided on in the past. Certainly the judge has the right to change the opinion (as in, go against what previous case law decided) but even in these instances, further case law must be cited to show why his opinion is different.
If a judge has a very strong personal conviction (partisan or not) about a certain case - he or she must prove that conviction with case law. *This is actually why superior court judges have to hire so many clerks - to do the research that backs up the opinion.* Emotion and raw opinion don't actually count. Also, I think there are times when judges actually rule against personal convictions because they cannot argue with strong enough evidence/research to back up their beliefs.
While complete and total impartiality is as elusive as any other ideal, one can only hope that the justices use the interpretation of the Constitution to help guide their decisions. Naturally, these interpretations are influenced by political biases, but the system is fairly rigorous to ensure that decisions are not made based on purely subjective ends, but actually rooted in a deep and profound understanding of the Constitution. The confirmation process is fairly intense in the assurance that the justices vote in accordance to their understanding of the Constitution, and the publication of decisions and disclosure of their rationale behind decisions helps to reflect Constitutional understandings, as opposed to using the bench as a place to espouse political beliefs at the cost of Constitutional understanding. In the end, I think that these are what helps to prevent partisanship from dominating the court discussion. The court ends up becoming the one realm that is the guardian of the Constitution.
There is no way to prevent personal convictions from influencing the way in which laws and the Constitution are interpreted. For example, can you say with certainty whether the First Amendment says that companies should be able to spend as much money as they like on ads about political candidates? All the Amendment says is that Congress can't abridge the right to free speech. What's that mean?
I certainly do not believe that the Court should allow literal partisanship. However, there are clearly different philosophies of judging that more or less correlate with party identity. As long as judges are acting based on their sincere beliefs about the law, there is no way we can really criticize them. The most difficult questions of law are really about belief and not about the law because the law is so vague.