In the United States, the cross-examining attorney is typically not permitted to ask questions which do not pertain to the facts revealed in direct examination. This is called going beyond the scope of the direct examination. Unlike in direct examinations, however, leading questions are typically permitted in a cross-examination, since the witness is presumed to be sympathetic to the opposing side.
In some formats used for structured debate, cross-examination is normally a three minute period in which the opposing team questions the case of the team directly after their eight minute speech. The purpose of this time is to clarify information, try to get the opposing team to make extreme comments, or not be able to answer. During policy debate there are four cross examination periods, one after each of the first four speeches.
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