I'm not sure exactly how law schools look at resumes, but I treated mine as a "fill-in-the-gap" sort of document. It looked nothing like any resume I have ever written in the past for employment consideration. I had already told the schools a lot about myself through my Personal Statement and other application questions, so I used the resume to really get into some details about my career acomplishments. Then again, I'm a musician with not much work experience outside restaurant employment. My resume focused on my music achievements (including producing audio CDs and developing new skills along the way, such as graphic design) and college education, and I barely touched on my work experience. In fact, I had a couple gaps in my employment that I didn't worry about too much. I figured it made more sense to focus on music achievements than to include 3 or 4 meaningless short-term jobs just to fill in time gaps in my employment history. Each situation is different, obviously, but I got accepted so the resume was good enough.
***Disclaimer: None of the above is meant to be legal advice, just one man's experience.