Who Stole The Cake?

I think Charlie stole the cake because he accused edward and then said that arnold didn't steal the cake so when Edward also agreed to say that Arnold didn't steal the cake then it only left us to believe that Derek Stole the cake Derek was left to say that both Charlie And Brian stole the cake but one of his answers had to be a lie and so when i went to go see Brian's answers he said it wasn't Charlie and it wasn't Edward but we already know it wasn't Edward so that statement was true and the LIE is Charlie DIDN'T steal the cake.