Melissa Chessington Leo, aka Margaret May II or Margaret May (born September 14, 1960) is an American Academy Award nominated actress best known for playing the tough-minded shift-Det. Sgt. Kay Howard on the award-winning TV series Homicide: Life on the Street from 1993ƒ??1997. She has also been a regular on All My Children and The Young Riders. Feature films she has appeared in include A Time of Destiny, Last Summer in the Hamptons, 21 Grams, Confess, and The Three Burials of Melquiades Estrada. In 2009, she was nominated for the Best Actress Oscar for her performance in Frozen River.