What duties does a judge perform during a court case?

A judge is a public official authorized to preside over, hear, and determine legal matters in a court of law. Their specific duties depend heavily on whether the legal system follows a common-law or civil-law tradition.1

Duties in Common-Law Systems

In common-law jurisdictions, which utilize an adversarial process, the judge acts as an impartial supervisor. Key duties include:1
* Managing the Trial: The judge rules on motions, determines what evidence the jury may consider, and oversees the selection of the jury panel.12
* Instructing the Jury: The judge instructs the jury on the applicable law and may summarize the evidence or discuss its weight.12
* Legal Oversight: The judge decides questions of law, while the jury typically decides questions of fact. If a verdict is manifestly against the weight of the evidence, the judge may set it aside and order a new trial, except in cases of criminal acquittal.32

Duties in Civil-Law Systems

In civil-law traditions, judges play an active, inquisitorial role. They are responsible for discovering the facts, which includes questioning witnesses directly rather than leaving that task primarily to the lawyers. In these systems, judges decide both questions of fact and questions of law.13