If you were given a PC that had nude pics/video on it, could you legally share it without getting into trouble?
Spoof your MAC address, go to the farthest free Access Point you know, go on 4chan/AnonIB, load your throwaway linux live distro and spam your pictures, go back home, smash your linux live media and sleep tight.
Why would he need to smash his Linux media? Live environment that millions of people use every day.
Why would he need to spoof his mac address? No investigations of that deep technical level will made unless of course this material is of underage nature.