Writer and Executive Producer Henry Louis Gates Jr. speaks at the Finding Your Roots With Henry Louis Gates, Jr. panel during the PBS portion of the 2012 Winter TCA Tour, held at the Langham Huntington Hotel and Spa Jan. 4, 2012, in Pasadena, Calif.  
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On Tuesday's episode of the PBS series Finding Your Roots With Henry Louis Gates, Jr., Benjamin Jealous, former president of the NAACP, learns how his great-grandfather Peter G. Morgan, a free black man, was forced to purchase his own wife and family in order to keep them safe.

Scandal actress Khandi Alexander never knew her grandfather but discovers through the research of Gates and his team that he may have been deliberately killed in the Jim Crow South.

Finding Your Roots With Henry Louis Gates, Jr. airs on PBS on Tuesdays at 8 p.m. EDT/PDT.