Can some one summarize this sentence pease asap white students were more likely to be disciplined for provable, documentable offenses — smoking, vandalism, and obscene language — while black students were more likely to be disciplined for more subjective reasons, such as disrespect.

Seems like you summarized it yourself

i don't think it's a good idea to threaten anyone at all.

dramatic irony occurs when the reader/audience knows more about a character's situation than the character does. the one main effect is that it gives the reader a sense of superiority, or detached superiority. the reader not only seemingly discovers what is revealed, but feels superior for doing so.