User blog comment:AltertheSilverBird/Total Drama: Danganronpa Chapter 7: Class Trial Part 2/@comment-27060311-20160809183902

By looking the comments / reading daily life I accuse....

I sincerely don't know, this case we have two possibilities that at least think of :

1- DJ is the killer, he gave Geoff the coffee in order to have an alibi in case he was found since Geoff was the person that bring it to Courtney.

2 - Geoff did it, during the time he was going to the cabin, he put the sleeping pills on the Coffee and set up his plan in motion.

I sincerely think its DJ, I think its more likely he did the plan and it seems comparing to Geoff that he had a reason to do it(namely the weapons cache/nuclear grenade thing + the fact he might missing his Momma from this point of the game) and also had the access to the following items to commit the crime.