led to the case of Prigg v. Pennsylvania, in which it was decided that their captors could supersede Pennsylvania's personal liberty law and claim ownership of the Morgans. This case highlighted the constitutional ambiguity of black rights while also illustrating the active effort by some in the white community to limit those rights. In New England, slave women went to court to gain their freedom while free black women went to court to hold on to theirs; the New England legal system was unique in its accessibility to free blacks and the availability of attorneys. Women's freedom suits were often based on technicalities, such as the lack of legal slave documents or mixed-race ancestry that exempted some from slave service. In New England in 1716, Joan Jackson became the first slave woman to win her freedom in a New England court. Elizabeth Freeman brought the first legal test of the constitutionality of slavery in Massachusetts after the American Revolution, asserting that the state's new constitution and its assertions of men's equality under the law meant that slavery could not exist. As a landowner and taxpayer, she is considered to be one of the most famous black women of the revolutionary era. Coverture limited the ability of some free black women to file lawsuits on their own, but a few women still filed jointly with their husbands. Notable free Negroes Born prior to 1800 Richard Allen: founder of African Methodist Episcopal Church, first independent black denomination in the US, co-founder of the Free African Society Benjamin Banneker: almanac author, astronomer, surveyor, naturalist and farmer. James Derham: first African American to formally practice medicine in the United States Elizabeth Freeman: healer, midwife and nurse who sued for her freedom in 1781 Prince Hall noted abolitionist for his leadership in the free black community in Boston, and as the founder of Prince Hall Freemasonry Thomas L. Jennings: first black man granted a U.S. patent Anthony Johnson (colonist): former slave who became a slave owner Absalom Jones: first ordained black Episcopal priest; saint John Berry Meachum: Baptist minister, businessman, educator Jane Minor, healer and emancipator Jean Baptiste Point du Sable: founder of Chicago and trader Lucy Terry: author Sojourner Truth: abolitionist and women's rights activist Denmark Vesey led a slave revolt in 1822 David Walker: abolitionist Phillis Wheatley: first published African-American female poet Theodore S. Wright: minister, co-founder of American Anti-Slavery Society 1800–1865 William