Bench trial
In jury trials, it is the judge's job to say what is the law and the jury's job to find the facts.  In a bench trial, the judge does both.  In some bench trials, both sides already agree on what the facts are.  For example, in civil disobedience cases designed to test the law, accused people often agree with the prosecuting lawyers about what happened.  They only want the judge to say whether it really was illegal.