The prime example of this is the legalization of gay marriage. The federal judges actually don't have the authority to create law, but they have begun to give themselves this authority by saying that something is "unconstitutional." It seems as though if I were one of these judges nothing would stop me from saying "it's unconstitutional for the president to make more money then me." The branch of government that's typically supposed to stop that type of law-making tyranny is...the judicial branch.
Some judges get so consumed in their power and make the wrong decisions instead of following the law and doing their jobs. Antonin Scalia was a great example of that. He rules according to his personal positions and not on the actual constitution. Judges can be very corrupt and not do their jobs.
For the greatest part, judges interpret the law fairly. There is a small minority of judges who interpret the law to their own ends and in their own opinions. Thankfully, when these cases come to light, these cases are overturned and in some cases the judges are asked to step down.
While I am sure there are many judges who do believe they are above the law, it is unfair to say that judges in general believe they are above the law. There are many lawyers, police officers, priests, business men, etc. who believe they are above the law, but that assumption does not apply to a whole group. In fact, there are people in power and people who have no education or money who believe they are above the law, but there are many who do not. Such a generalization statement about the whole group is unfair.