blue ribbon jury

Definition from Nolo’s Plain-English Law Dictionary

A jury consisting of persons with special qualities, such as advanced education or special training, sometimes used in complicated civil cases (with the parties' consent) and to investigate suspected governmental corruption. Specialists in a technical field are called a "blue-blue ribbon jury." Blue ribbon juries are not allowed in criminal cases, because doing so would violate a defendant's right to be tried by a jury of his peers.

Definition provided by Nolo’s Plain-English Law Dictionary.