This paper describes the design and evaluation of Shared Speech Interface (SSI), an application for an interactive multitouch tabletop display designed to facilitate medical conversations between a deaf patient and a hearing, non-signing physician. We employ a participatory design process involving members of the deaf community as well as medical and communication experts. We report results from an evaluation that compares conversation when facilitated by: (1) a digital table, (2) a human sign language interpreter, and (3) both a digital table and an interpreter. Our research reveals that tabletop displays have valuable properties for facilitating discussion between deaf and hearing individuals as well as enhancing privacy and independence. The contributions of this work include initial guidelines for cooperative group work technology for users with varying hearing abilities, discussion of benefits of participatory design with the deaf community, and lessons about using dictated speech on shared displays.