William & Mary asks you to write an essay to "describe an event in your life of which you are especially proud."
It also requests an optional essay on one of 4 things: Institute of Bill of Rights Law, Courtroom 21, Law Library, or George Wythe Society of Citizen Lawyers.
I actually ended up not applying because the school's application was so weird, and I received an acceptance from a higher choice school of mine before I got my act together enough to apply there.
Opinions may vary as to whether optional essays are really optional, but I would really recommend writing a page or two any chance you get. It's an opportunity to showcase your writing abilities, and also to give your application a little extra bump if you're not an auto-admit. Even if your numbers are auto-admittable for a school, you're more likely to get waitlisted by a school, which may assume they're just your safety and could waitlist you to yield-protect.