What is the role of a judge?

In cases with a jury, the judge is responsible for insuring that the law is followed, and the jury determines the facts.

In cases without a jury, the judge also is the finder of fact and has to listen to the evidence without passing judgment until all sides of the story are heard,

A judge is to be impartial, fair and unbiased and to follow the laws of the state they are in and the United States Constitution and the Constitution of whatever state they are in.