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Boston University School of Law




The Model Penal Code approach to mens rea was a tremendous advance. The MPC carefully defines a limited number of mens rea terms, firmly establishes element analysis in place of offense analysis, and recognizes that the doctrine of mistake is part and parcel of the basic analysis of mens rea.

However, a revised Code could improve the drafting of the mens rea provisions in a number of respects:

* Clarify how to distinguish result, circumstance, and result elements

* Simplify the definitions of knowledge and purpose

* Perhaps eliminate the category of mens rea as to conduct

* Clarify the fact/law distinction, and especially the distinction between two types of mistakes of law - mistakes of governing law and mistakes of legal element - that the MPC treats differently

* Clarify the meaning of the "reasonable person" test

* Clarify the definition of willful blindness

Moreover, more fundamental questions arise with the central concept of recklessness. A reckless actor is one who must be aware of a "substantial and unjustifiable" risk; are these independent or interdependent requirements? What type or degree of consciousness is required? Of what, precisely, must the actor be aware? Does a strict "consciousness" requirement undermine the rule that ignorance of law is no excuse? And shouldconsciousness extend to "latent" knowledge that the actor could call up if he were to consider the matter even for a moment?

Furthermore, does the MPC hierarchy always work? Is knowledge really always worse than recklessness? Is recklessness always worse than negligence? Should culpable indifference or a similar mental state be added tothe hierarchy? Are the MPC categories too cognitive, or too descriptive, or too rigid? Finally, the conclusion examines some theoretical and pragmatic implications of the analysis.



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