Steve pointed me to the Illinois Supreme Court's opinion in People v. Cole, which holds that the Cook County Public Defender is not a "firm" within the meaning of Illinois Rule 1.10, which is substantively the same as the ABA model rule. As a practical matter, the holding means that different members of the PD's office may have to represent clients who are charged together but who have antagonistic interests.
The case came up from a friendly contempt citation issued to the Cook County PD, who had asked that the court not appoint the PD's office to represent one client (Cole) because the office already represented four other defendants. (The office eventually moved to withdraw from representing them.) The NACDL filed an amicus brief, as did the National Association for Public Defense, and three professors, including Steve.
This opinion makes sense to me but I respect the judgment of people on the other side of the issue, so I thought it might be interesting to discuss on the blog.