By Brendan J. Coffman*

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INTRODUCTION

A man sits in his apartment in a major United States city checking his email. He may or may not be a U.S. citizen, and may or may not be associated with a significant international organization. The government’s intelligence agencies are not aware of the man, and local police officials have no overt reason to suspect anything abnormal or threatening. His email is transmitted and stored by a major electronic communications service provider, and his private messages on the server contain information vital to his plot—to attack a major U.S. city.

In the adjacent apartment, a man sends an email to a friend discussing his desire—mostly imaginary, but frighteningly realistic—of assaulting his female neighbor. The friend’s wife intercepts the email. The wife does not believe the man would follow through on his desires, and goads him on in response. Much like the case above, the police have no reason to suspect any dangerous intention from this man.