moot court

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A mock court where hypothetical cases are tried for the training of law students.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun law In law school, an activity wherein students compete by making arguments with respect to a hypothetical case, or a case that has already been decided by an actual court.
• noun law A law school organization which organizes such competitions and prepares competitors.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a mock court where law students argue hypothetical cases