A protective case for an electronic device having an antenna includes a first case member and a second case member. The first case member includes at least two metallic case portions joined to each other by at least one electrical insulator segment that electrically isolates the at least two metallic case portions from each other to reduce electromagnetic interference between the first case member and the antenna of the electronic device. The second case member that attaches to the first case member to form an enclosure that at least partially encloses the electronic device when the electronic device is installed in the protective case.