In reviewing the criminal justice systems of many countries one can easily see the difference between the duress and necessity. For example in France, duress is used as an excuse whereas necessity is used as form of justification.
The difference between these two forms of defense is the reaction of endangered individual .In order for an individual to use necessity as form of justification, it is important that the reaction of endangered individual must supersede the outcome of present danger, however this is not required in person with duress. In other words the least of two evils must be considered.
In other countries like United States a model penal code is used. In this law, necessity and duress are used as part of justification, if the reaction of endangered person is more beneficial to the situation but in absence of the above requirement in necessity will result in less punishment. It is important to notice that the most advanced form of justice system in this regard is Germany.
In German judicial system there is no difference between the necessity and duress as long as the reaction of endangered individual is proportionate to the threat. In that case it can be used as part of justification; otherwise it is used as an excuse.
In Iranian justice system, the legislative body does not recognize the duress and necessity as part of any forms of justification; rather it is seen as an excuse.
Regarding the basic criminalization and justification, it is necessary that if the reaction of an endangered individual supersedes the outcome of a danger or threat then it must be considered as a justification. This important issue however is not discussed in our judicial system but the courthouses and judges can take this issue into consideration.
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