1) Credited screenwriter David Franzoni received a copy of Echo of Lions.
2) Franzoni worked with Punch Productions for six to eight months as a writer on the "Echo of Lions Project" while Punch was licensed to use Chase-Riboud's book and helped pitch this project to Warner Bros.
3) Franzoni's screenplay for Amistad contains historical "errors" also contained in Echo of Lions, including:
a) a letter from Queen Victoria to President Martin Van Buren;
b) the portrayal of the interpreter as a person that speaks near-perfect English; and
c) the number of children Cinque had.
4) Amistad and Echo of Lions contain the same fictional character--a wealthy, erudite black man involved with the printing of abolitionist literature.
5) An early Amistad shooting script was titled "The Other Lion."
A motion to block the opening of Amistad was shot down by a U.S. District Court judge who found that 1) the similarities between the two works were not substantial 2) fictional characters cannot be copyrighted, and 3) Amistad's screenwriters rendered the similarities irrelevant.
The judge ruled that the suit has virtually no likelihood of success.