Let's imagine the following situation:
"Overintelligent hacker connects to Wi-Fi points across country and performs illegal activities that get government's attention.
If all the government can get is routers' logs which IP was assigned and connected, it is still internal IP. Now let's assume they exposed hacker's MAC address which was faked."
How can investigators solve the puzzle?
Can that hacker be traced and if he can, then how? And does ISP stores router's MAC address in its database for tracing?