Professor Rosenthal filed a friend-of-the-court brief in the United States Supreme Court on behalf of the International Municipal Lawyers Association, the National Association of Counties and the National League of Cities in the case of Rehberg v. Paulk.  At issue in this case is whether a law enforcement official can be held liable for damages based on allegedly false grand jury testimony. The brief argues that in light of the many safeguards offered by the criminal law and the threat to the interests of law enforcement and the taxpayers if civil liability for testimony were imposed, the Court should apply the longstanding rule of testimonial immunity to this case.