After charges have been declared, if any Impetuous units did not declare a charge but are within charge range of an enemy, then they must take a Leadership test to restrain themselves from charging. If this test is failed, they are forced to charge. If the test is passed, they may move normally.
So reckless are the Knights Errant that whenever they charge, they have Immunity (Psychology) and may re-roll one of their charge distance dice.