Is it a federal offense to threaten bodily harm to another person via
email?  If so, what is the law that prohibits it?

Hello oliveoyl-ga,

At the outset, I should emphasize the disclaimer at the bottom of this
page, which notes that answers and comments on Google Answers are
general information, and not substitutes for professional legal
advice.  If you need a professional opinion, you should consult an
attorney in your area.

According to the information I have seen, 18 U.S.C. Sec. 875(c) makes
the conduct described in your question a federal crime under certain
conditions.  This statute states:

"Whoever transmits in interstate or foreign commerce any communication
containing any threat to kidnap any person or any threat to injure the
person of another, shall be fined under this title or imprisoned not
more than five years, or both."

"Title 18 > Part I > Chapter 41 > Sec. 875"
Legal Information Institute (LII)
http://www4.law.cornell.edu/uscode/18/875.html

It appears (and again, remember that I cannot give a professional
opinion) that the Jake Baker cases indicate parameters of what an
e-mailed "threat" is, while the Kammersell case indicates how
"interstate ... commerce" might apply even to some seemingly
intrastate communications.

"United States v. Alkhabaz" [U.S. Court of Appeals opinion in Baker
case]
The Berkman Center for Internet & Society at Harvard Law School
http://cyber.law.harvard.edu/ilaw/Speech/Baker2.html

"United States v. Baker" [U.S. District Court opinion in Baker case]
Stuart Beraha's Lazy Homepage [an odd sounding source, but its link is
on a relevant FindLaw page:
http://cyber.findlaw.com/criminal/cyberstalk.html ]
http://ic.net/~sberaha/baker.html

"United States v. Kammersell"
Kansas Judicial Branch
http://www.kscourts.org/ca10/cases/1999/11/98-4177.htm

I hope that this information is helpful.

- justaskscott-ga


Search terms used on Google:

"federal crime" threat e-mail
"18 U.S.C. 875"
18 875 interstate threat e-mail 
baker kammersell
alkhabaz kammersell

The answer gave me just what I needed:  a quick reference to a federal
statute.  I would have been happy with that alone.  But the researcher
also provided free web sites to three key cases.  And all was done
within one hour.  I was not looking for free legal advice -- simply a
quick sign post to the appropriate standards.  Thank you very much.