Are you asking if Hodges should be held responsible for the student's actions?
He's responsible for HIS computer. Obviously he supervised the kid doing the search.
The guy COULDN'T do a Google and find the video, and it was linked in about all the news sites. I doubt he had "secure" access to his machine and the student reportedly did the finding before the start of the class. The teacher probally didn't even realize just how horrific the act shown on the video was.