What is the role of a judge in the context of a civil trial?

"A judge, at least in a federal court, is more than a moderator; he is affirmatively charged with securing a fair trial, and he must intervene sua sponte to that end, when necessary. It is not always enough that the other side does not protest; often the protest will only serve to emphasize the evil. Justice does not depend upon legal dialectics so much as upon the atmosphere of the court room, and that in the end depends primarily upon the judge."

Brown v. Walter, supra, at 799-800.

13 See also note 15, infra.