The capture of the three slave ships occurred one year before the passage of the Act of 1819 which equated the slave trader with a pirate and made the penalty for participating in the African slave trade the same as piracy, punishable by death. ( In 1862, the last man hanged in the U.S. for piracy in New York City. He was a slave trader. https://en.wikipedia.org/wiki/Act_to_Protect_the_Commerce_of_the_United_States_and_Punish_the_Crime_of_Piracy