Duress or Necessity

(a)In a prosecution for any offense it is an affirmative defense that the defendant engaged in the conduct otherwise constituting the offense:

(1)because he was coerced into doing so by the threatened use of unlawful force against his person or the person of another in circumstances where a person or reasonable firmness in his situation would not have done otherwise; or

(2)in order to avoid death or great bodily harm to himself or another in circumstances where a person of reasonable firmness in his situation would not have done otherwise.

(b)The defenses defined in this Section are not available if the offense is murder nor to a person who placed himself intentionally, knowingly or recklessly in a situation in which it was probably that he would be subjected to duress or compulsion.