Academic journal article Vanderbilt Law Review

Humpty Dumpty on Mens Rea Standards: A Proposed Methodology for Interpretation

Academic journal article Vanderbilt Law Review

Humpty Dumpty on Mens Rea Standards: A Proposed Methodology for Interpretation

Article excerpt


"When I use a word. . it means just what I choose it to mean-neither more nor less."1

This statement by Humpty Dumpty sets forth the argument of this Note: words used to describe mens rea in federal criminal statutes have plain, ordinary meanings. When the United States Supreme Court interprets these statutes, it should do so according to the words' plain meanings. Because the Court has not used this approach in past cases, the law of mens rea on the federal level is confusing and inconsistent.

The Court has tried to repair poorly drafted statutes by interpreting them in various ways to achieve what it thought was the correct result. By applying different interpretation techniques, however, the Court has developed an ad hoc mens rea jurisprudence that confuses people about what mental state is necessary for conviction under federal criminal laws. People thus cannot order their affairs to avoid violating the law. To clarify the law, the United States Congress and the Supreme Court should engage in a law-making dialogue that results in Congress drafting clearer statutes and the Court interpreting those statutes according to the words' plain meanings.

The Supreme Court's mens rea analysis in federal criminal cases is least settled in cases involving the "knowingly" standard. The Court apparently interprets other mens rea standards, such as "willfully," "purposely," and "recklessly," consistently. The Court has more difficulty interpreting "knowingly," because it falls in the middle of the mens rea standard hierarchy.2 "Willfully," the most stringent standard, implies either a full understanding of both the law and the facts3 or an understanding of egregious facts that indicate the defendant knew she was doing something wrong.4 "Recklessly," one of the lowest standards, implies very little thought.5 "Knowingly," however, indicates a standard somewhere above recklessness and below fully-informed thwarting of the law. Determining exactly what it means to act knowingly appears to be difficult for the Court.6

Although the Court has consistently defined "knowingly" to require that the defendant actually knew he committed the acts that made his conduct criminal,7 the Court applies this definition only if doing so will allow the Court to reach its desired result.8 For instance, when the Court hears a case involving a statute that criminalizes morally suspect behavior,9 it defines "knowingly" to require only that the defendant knew he acted, regardless of whether the defendant knew those actions were illegal.10 In cases that involve statutes that may be read as criminalizing otherwise innocent conduct,11 the Court defines "knowingly" to mean that the defendant knew the facts about his or her actions and that those actions were illegal.12

In this latter set of cases, the Court allows ignorance of the law to be a defense to criminal liability even though one of the basic premises of criminal law is that people are presumed to know the law. Valid reasons why the Court requires knowledge of the law in certain cases include: not requiring it would criminalize too much behavior13 or would result in the statute being unconstitutional.14 The Court thus preserves statutes by interpreting their mens rea requirements in an ad hoc rather than a consistent manner. At the same time, the Court leaves a patchwork of precedent that results in no fixed law on which the Court, lower courts, or lay people can rely for guidance about how the "knowingly" mens rea standard will be interpreted in federal criminal cases.

A survey of the mens rea issues that have come before the Court in federal criminal cases in the last ten years shows the unsettled state of the law. This case law demonstrates that the Court applies a variety of definitions to the word "knowingly" and that it approaches mens rea issues inconsistently.15 In some circumstances, the Court looks at legislative history to try and determine the congressional intent behind a statute. …

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