That is just what happened to residents of Marin County, California. As this article details, they gave out their wifi password to their friend, Mark Magner, who then downloaded child porn while on their network. The Internet Crimes Against Children task force say the child porn traffic on the internet and traced back the IP address to the home in Marin County. When police served a search warrant on that house, no child pornography was found. That is because Mr. Magner had left and took the computer he used to download the illegal content with him.
What the article doesn’t mention is what happens when a search warrant like that is carried out. Police will seize all electronic devices – computers, laptops, tablets, etc. They will then search these devices for evidence of child pornography. These searches could take weeks, leaving you without a way to do your work from home. If you have a business computer at your home, that computer could also be seized, along with all of your work.
These residents in Marin County might consider themselves lucky. While they had a search warrant served on them, at least they didn’t have the SWAT team throw flashbangs and raid their house, like what happened in this case in Evansville, Indiana.
How do events like this happen?
You’ve probably heard the term used before. IP Addresses are the key to how traffic on the internet knows where to go. They serve as your address on the internet. When you go to a website and download a file, that web server gets your IP address. It then sends the file to your IP address, like putting your mailing address on a package. When you send an email, your IP address is included. When you post a comment to a website, your IP address is logged.
When you have a wireless network, everyone on that network is using the same IP Address. That means, whatever you, your spouse, your children, or your guests do on the Internet, all uses the same IP Address. So if a guest uses your wireless network to send a threat through email on the Internet, that threat will be traced back to your house.
It is important that you take steps to protect your wireless network. Set strong passwords, and only give them out to people you trust.
If you are a lawyer in a case dealing with online evidence and IP Address tracing, make sure you understand how IP Address work. An IP Address traces back to a physical address, not to a specific individual. If you want to prove that a specific individual did or did not do something online, you need to have more information than just an IP Address.