Houseguest downloads child porn, cops show up
Do you really know how your various friends, relations, acquaintances, and hangers-on plan to use your Internet connection when they drop by and ask for "the Wi-Fi password"? Unlikely—and yet anything that they do illegally through your home network can bring cops to your door with search warrants, asking tough questions about child pornography.
Case in point: Marin County, California, just north of San Francisco's Golden Gate Bridge. Local police in Marin communities like Novato are members of the regional Internet Crimes Against Children (ICAC) task force, and as such they participate in the common law enforcement practice of monitoring peer-to-peer file-sharing networks for possible child pornography files. In September 2013, Novato detective Amy Yardley was looking for such files being traded from Marin County IP addresses, and she scored a hit on the Ares network with a suspicious file downloaded by a Sausalito Internet subscriber.