Federal Rules of Civil Procedure Rule 38 establishes the right to a jury trial in civil cases, which is a critical component of the judicial process. This rule ensures that parties in a civil action can demand a jury trial for issues that are properly triable by a jury, thus reinforcing the principles of fairness and impartiality in legal proceedings. By guaranteeing this right, Rule 38 plays an essential role in closing arguments, as the jury's perceptions and conclusions are heavily influenced by the arguments presented during this final stage of a trial.