From the Document: "There has been increased discussion about law enforcement legally 'hacking' and accessing certain information about or on devices or servers. Law enforcement has explored various avenues to discover and exploit vulnerabilities in technology so it may attempt to uncover information relevant to a case that might otherwise be inaccessible. For instance, as people have adopted tools to conceal their physical locations and anonymize their online activities, law enforcement reports that it has become more difficult to locate bad actors and attribute certain malicious activity to specific persons. As a result, officials have debated the best means to obtain information that may be beneficial to the administration of justice. Exploiting vulnerabilities is one such tool. [...] Congress may examine a range of policy issues related to law enforcement using and disclosing vulnerabilities. For example, how does law enforcement's ability to lawfully hack, or exploit vulnerabilities, influence the current debate surrounding whether law enforcement is 'going dark,' or being outpaced by technology?"
CRS Report for Congress, R44827
Federation of American Scientists: http://www.fas.org/sgp/crs/index.html