To determine your eligibility for the most common sources of aid (e.g., the Stafford Loan), schools will apply what is called the Federal Methodology. In a nutshell, this set of criteria set forth by the federal government uses your statement of income, assets, and financial liabilities to determine what is called your Family Contribution. This is the amount of money that a school will expect you (and, if applicable, your spouse) to contribute to the financing of your legal education. Since it does not include the Parental Contribution (PC), however, the Family Contribution (FC) is sort of a misnomer for many applicants coming directly out of college and for all applicants to certain schools.
If you have never applied for financial aid in the past and are operating under the assumption that, as a tax-paying grown-up x number of years out of school, you will be recognized as the self-supporting adult that you are, well, you've got some growing up to do.
Veterans of financial aid battles past will not be surprised to hear that financial-aid offices have a difficult time recognizing when apron strings have legitimately been cut. Some schools will consider your parents' income in determining your eligibility for financial aid, regardless of your age or tax status. Policies vary widely, so be sure to ask the schools you consider closely what their policies are regarding financial independence for the purposes of determining financial aid eligibility for the school's own money.
Only federal financial-aid standards for independence are simple and consistent. You are automatically considered Independent for purposes of federal aid (e.g., Perkins or Stafford loan programs) as a graduate student. It doesn't matter if you still live with your parents or even if they claim you as a dependent. You will be seen as independent in the eyes of the federal goverment. Again, these standards apply only to federal financial aid (Stafford and Perkins loans).
A few of the very selective schools will insist on seeing parent information anyway. The Harvard Law School FAOs, for example, require parents' financial data even if the student is forty years old and the parents have long since retired to Miami Beach. Though the schools may refuse to give you any of their own money, you can still qualify for Stafford loans by meeting the federal regulations for independent status.