The biggest thing I've learned from good lawyers, is that with the law - there's always an appeal, a different interpretation, and a challenge or request for exemption from a rule.
Applying to be a lawyer in and of itself can be a process of figuring out the correct paperwork to fill out and asking for a special exemption on a piece of missing information or a missed deadline.
Police discretion is a great example imho. Watch everywhere in your day to day as laws are applied based on a subjective real time evaluation of the situation.