if you had to work, you could always use an addendum to explain it. schools won't mind, and they'll probably appreciate the clarification. If you're giong to law school straight from undergrad, i think you can do what you damn well please as long as you graduate.
if you're planning on taking a year or more it may be worth just finishing out.
If you don't explain (BRIEFLY!!! Like, in 2 - 3 sentences max!) they will assume the worst. So by all means explain. Briefly! And if it's your last semester will they even see it before making a decision? Are you applying this cycle?
No. Next cycle. I am taking next year off to work (I am currently working, but hoping to get this new job I am applying for this upcoming week *crosses fingers*).