4 examples of people who have used Tor for illegal activities and how they were caught. Multiple de-anonymization attacks are shown at the end of the video. Part 2 can be found here https://www.youtube.com/watch?v=TQ2bk… 
You can read more about the cases here: http://se.azinstall.net/2015/11/how-t…

Case 0: Harvard bomb threat Eldo Kim getting busted by being one of the only users at Harvard on the tor network, and admitting he emailed the bomb threat.
Case 1: Hector Xavier Monsegur (Sabu) and Jeremy Hammond LulzSec getting caught for logging on to IRC one time without tor and FBI using correlation.
Case 2: Freedom Hosting admin under attack from Anonymous group previously fighting CP might have helped the FBI, later they skip to when a box was compromised and made it host a javascript exploit. Nothing mentioned what happened between the Anonymous attacks and when the FBI smashed in his door.
Case 3: Silk Road creator Ross Ulbricht (Dread Pirate Roberts) making too many mistakes including using his own real name then changing it later to a username.