Morissette lived near a
bombing range. He entered the range, took some shell fragments he found
lying around, and sold them as scrap metal.
When the Air Force found out
what happened, he was arrested and charged with "knowingly
converting" government property (18 U.S.C. §641)
Morissette argued that he
thought that the shell fragments were abandoned property.
The Trial Judge instructed the
jury that in order to convict they had to find that Morissette intended to take the shells, not that he intended to "knowingly convert" (aka steal)
someone else's property.
The Trial Court convicted
Morissette. He appealed.
The Appellate Court affirmed.
The Appellate Court found
that the term "knowing conversion" should have its traditional
tort law meaning, simply an intentional exercise of dominion over
property that is not one's own.
The US Supreme Court reversed.
The US Supreme Court found
that §641 should be read to
require intent as an element, even if it is not explicitly
stated in the Statute.
The Court found that strict
liability has traditionally only be
used in very minor offenses (such as parking tickets), and the historical
common la has always required intent (aka mens rea) for
crimes involving theft.
The Court noted that there
was no bright line rule for which offenses required mens rea.
Basically, this case said that
for relatively serious crimes, there must be a mental element on the part
of the defendant to commit a crime (aka mens rea). You cannot be found guilty of a crime just
because you physically committed the act (aka strict liability)
Even though Morissette did
take the government property, he wasn't trying to steal it, and he cannot
be found guilty.
For example, if you are a
professional juggler, and you are juggling chain saws, and you drop one
and it kills somebody, you won't be guilty of murder because you weren't
trying to kill someone.
On the other hand, for minor
infractions such as parking tickets, you can be found guilty even if you
honestly thought you were parked legally.