I remember seeing something like this online. I think it was murderpedia.org ?
Details are a bit fuzzy and might be wrong. In the 90's someone murdered a person or two. Somehow the cops asked the local ISP for anyone making constant searches of the case. They traced it back to the murderer.
I was kind of wrong on the details, was in 2002 and they asked Microsoft.
"Instead, agents simply tapped into the wealth of information that Microsoft Corp. and other Internet companies keep on people who visit their Web sites and use their services."
Details are a bit fuzzy and might be wrong. In the 90's someone murdered a person or two. Somehow the cops asked the local ISP for anyone making constant searches of the case. They traced it back to the murderer.