In 1836, Mary Aves Slater of New Orleans went to Boston to visit Thomas Aves, her father. She brought with her a six-year-old girl named Med who, under Louisiana law, was considered the property of Slater's husband, Samuel Slater. When members of the
Boston Female Anti-Slavery Society learned that an enslaved girl was staying in Boston, they hired attorney
Rufus Choate to bring the matter to court. Choate was joined by abolitionist attorneys
Ellis Gray Loring and
Samuel E. Sewall.
Benjamin Robbins Curtis, later known for his dissent in the
Dred Scott decision, represented Aves. Curtis argued that the
doctrine of comity required Massachusetts to respect the laws of Louisiana, and therefore Mrs. Slater should be allowed to bring Med home with her. Loring argued that the comity principle did not apply "in doubtful cases," and that there was no consensus on slavery; England and several other European nations had a policy of "disregarding the
lex loci in the case of slaves," giving them "immediate and entire liberty" when they were brought there from another country. He characterized slavery as immoral, and expounded on the commonwealth's longstanding commitment to liberty. When giving his opinion, Shaw discussed several precedents in international law, including the British case of
Somerset v. Stewart (1772), and the abolishment of slavery in Massachusetts. The only people who could be treated as slaves in Massachusetts, he reasoned, were fugitive slaves, and then only because the U.S. Constitution specifically required it. Therefore, Med had become free as soon as her alleged owner voluntarily brought her to Massachusetts. He cited several cases demonstrating that even in Southern states it was understood that a slave became free when voluntarily brought to a free state.
Commonwealth v. Aves was later used as a precedent in other Northern states. Connecticut used it in
Jackson v. Bulloch (1837); New York and Pennsylvania used it in legislation declaring that slaves became free when brought to those states; and Ohio courts began using it in 1841. By the start of the Civil War, every Northern state other than Indiana, Illinois, and New Jersey granted freedom automatically to any slave brought within its borders. Med was placed in the custody of the abolitionist women, while her mother and siblings remained enslaved in New Orleans. The women renamed her Maria Somerset, after
Maria Weston Chapman and the
Somerset case. At some point later she was moved to an orphanage. == See also ==