Shield Act - Amends the Uniform Code of Military Justice (UCMJ) to permit a Special Victims' Counsel who is representing an alleged victim of a rape, sexual assault, or forcible sodomy offense to speak on behalf of such victim in a preliminary criminal investigation (Article 32 Investigation) of any such offense when the victim has the right to be heard. Prohibits: (1) questions during such investigation about the sexual behavior of an alleged victim that is not directly related to the charge or specification being investigated, or (2) the admission of any evidence to prove or show a sexual predisposition on the part of an alleged victim.