Halla Ettyk was a Human female New Republic commander and criminal prosecutor from Alderaan who fought against the Galactic Empire during the Galactic Civil War. She survived the Death Star's destruction of her homeworld by being off-planet trying to depose a witness. The loss of the peaceful planet helped motivate her to join the Alliance soon afterward.
Ettyk rose through Airen Cracken's intelligence organizations to the rank of Commander. Circa 7 ABY the Alderaanian was working on the recently liberated capital planet Coruscant and upon being offered the job of prosecutor on behalf of the New Republic Armed Forces in the Trial of Tycho Celchu, immediately signed on, despite having not prosecuted a case in seven years.
The commander presented seemingly overwhelming evidence that Captain Tycho Celchu was guilty of the murder of Corran Horn, and of treason against the New Government. The politically-motivated case (being used by the government to show they could be as hard on Human criminals as they could on aliens in the face of the Krytos virus) seemed almost impossible for defense attorney Flight officer Nawara Ven to win, even with Ettyk using mostly circumstancial evidence, a testament to her legal skills.