Buck performs a significant act

Buck accidentally or impulsively kills someone.

Mistaken judgment-through his own actions- Buck takes an action that results in trouble.

A normal seeming act on Bucks part has unexpected consequences.

Buck ignores, breaks, or sidesteps a taboo, command, custom or rule - he transgresses

Buck performs a consequential act under the influence of a mind altering substance or state

Buck commits a crime or transgression without desiring to do so