A person may not be convicted of an offense, other than a class 1 felony, based upon conduct in which he engaged at the direction of another person because of the use or threatened use of unlawful force upon him or upon another person, which force or threatened use thereof a reasonable person in his situation would have been unable to resist. This defense is not available when a person intentionally or recklessly places himself in a situation in which it is foreseeable that he will be subjected to such force or threatened use thereof. The choice of evils defense, provided in section 18-1-702, shall not be available to a defendant in addition to the defense of duress provided under this section unless separate facts exist which warrant its application.