Free supplemental preparation for the New York state bar examination could soon become a thing of the past for minority candidates who have depended on a special program offered through a small nonprofit agency since 1991.

Amanda Samuel, chairwoman of Practicing Attorneys for Law Students, said her organization’s special tutorial budget could disappear in three years unless $100,000 from new law firm donors can be raised to sustain it. The program affects about 120 students per year.