Search Warrants Authorizing Law Enforcement Computer Hacking and Malware

Suppose that law enforcement becomes aware of criminal activity taking place through a website, like the distribution of child pornography or the sale of illegal drugs. Can officers use computer hacking techniques and malware to identify users who accessed the website? Would the officers need a search warrant to do that? What kind of a search warrant? This post tackles those questions. Playpen. Most of the case law in this area stems from the federal government’s investigation of a child pornography website called Playpen. In early 2105, the FBI took the website over. It operated the site for two weeks – a decision that later generated immense controversy – during which time it deployed malware on users’ computers. (The government uses the term “Network Investigative Technique (NIT)” rather than malware, but there is no dispute that the government installed uninvited, unwelcome, and undisclosed code on users’ computers, exploiting a security vulnerability in their web browsers.) The malware collected users’ IP addresses and other information and sent it to the FBI, enabling the FBI to identify and further investigate the users. The FBI had obtained a federal search warrant authorizing the use of the malware, but users who were identified and prosecuted as a result of the use of the malware challenged the warrant on several grounds, including lack of particularity and lack of territorial jurisdiction. These cases are working their way through the federal courts now. The most common outcome has been for courts to find that even if there was [...]