The history of crime in America has proven that criminals are often the first to seize upon opportunities presented by new technologies and use them for nefarious purposes. It has also shown that law enforcement groups are quick to respond and use high-tech tools to defend the public safety. This work is a comprehensive survey of how the underworld takes advantage of new tools and techniques and how authorities can fight back, prevent crime, and capture criminals. In more than 420 entries, it covers DNA and medical evidence to computer virus attacks, from blood spatter analysis to explosive detection devices.