Below are some of the law school representation stats:
Harvard Law: Northwestern 20, JHU 3
Yale Law: Northwestern 8, JHU 0
Virginia Law: Northwestern 3, JHU 1
Michigan Law: Northwestern 20-29, JHU 10-19
Georgetown Law: Northwestern 10, JHU 3
UCLA Law: no exact number but Northwestern is listed as one of the top represented schools
USC law: Northwestern 4, JHU 0
http://www.law.harvard.edu/admissions/jd/colleges.php (no longer exists; use web archive)
Law School Students Class of 2009 Profile faq-charts Georgetown Law - Profile of the 2002 Entering Class (Admissions) 2007 Incoming Class Profile | Admissions Information | UCLA Law http://law.usc.edu/admissions/assets...006profile.pdf
I'd give the edge to NU for law school admission. NU also has one of the top law schools and even though there's no stats available, it's safe to assume NU undergrad is the top represented school for NU law.