"It is difficult to conceive of a more textbook violation of this rule than when an attorney for the commonwealth fails to correct a pivotal law enforcement witness's false denial of knowledge about facts that she herself provided to the witness in their pretrial preparation session," the complaint states. "Here, Ms. Kirn stood mute while not one, but two, of the commonwealth's most critical witnesses perjured themselves in this fashion. And she did so as an experienced homicide prosecutor, serving as lead counsel for the commonwealth in a case where the defendant faced mandatory life in prison without the possibility of parole if convicted."