When the Cops Come A-Knocking: Handling Technical Assistance Demands from Law Enforcement

What kind of surveillance assistance can the U.S. government force companies to provide? This issue has entered the public consciousness due to the FBI's demand in February that Apple write software to help it access the San Bernardino shooter's encrypted iPhone. Technical assistance orders can go beyond the usual government requests for user data, requiring a company to actively participate in the government's monitoring of the targeted user(s).