An American slave who sued for, and won, his freedom.
An American slave who sued for, and won, his freedom in Massachusetts by using the deceleration that "all men to be born free and equal".
Important because it was a case credited to abolishing slavery in Massachusetts.
Anything else--supplemental info, memory pegs, etc.
case won in 1781, if you're trying to remember it with a name game, try thinking of how Quock Walker 'walked' away from slavery, thanking the 'quak'ers.