The Correspondence of Thomas Jefferson

By Subject

AFRICAN AMERICANS / MULATTOS DEFINED BY LAW

You asked me in conversation, what constituted a mulatto by our law? And I believe I told you four crossings with the whites. I looked afterwards into our law, and found it to be in these words: "Every person, other than a Negro, of whose grandfathers or grandmothers anyone shall have been a Negro, shall be deemed a mulatto, and so every such person who shall have one-fourth part or more of Negro blood, shall in like manner be deemed a mulatto;" L. Virga' 1792, December 17; the case put in the first member of this paragraph of the law Is exempli gratid. The latter contains the true canon, which is that one-fourth of Negro blood, mixed with any portion of white, constitutes the mulatto. As the issue has one-half of the blood of each parent, and the blood of each of these may be made up of a variety of fractional mixtures, the estimate of their compound in some cases may be intricate, it becomes a mathematical problem of the same class with those on the mixtures of different liquors or different metals; as in these, therefore, the algebraical notation is the most convenient and intelligible. …

…Our canon considers two crosses with the pure white, and a third with any degree of mixture, however small, as clearing the issue of the Negro blood. But observe, that this does not re-establish freedom, which depends on the condition of the mother, the principle of the civil law, partus sequitur ventrem, being adopted here. But if emancipated, he becomes a free white man, and a citizen of the United States to all intents and purposes. So much for this trifle by way of correction.

to Francis C. Gray, 4 March 1815