The series showed the workings of the judicial system, beginning with the arraignment, and continuing through the lawyers process of building a case, investigating leads, and preparing witnesses and defendants for trial.

Lennie Briscoe (Jerry Orbach), now retired from the N.Y.P.D., joins the District Attorney's office as an investigator. Through him, and the various lawyers, jury members and court officials we meet along the way, the show explores the intricate workings of the jury system.