Roll was elevated to Chief Judge on May 1, 2006, succeeding Stephen M. McNamee, and served until his death in January 2011.

[11] In 1994, Roll was one of several district court judges who held that provisions of the Brady Law violated the Tenth Amendment,[12] a holding upheld by the United States Supreme Court in the related case of Printz v. United States.

The $32 million lawsuit brought by the Mexican American Legal Defense and Education Fund (MALDEF) against Arizona rancher Roger Barnett on behalf of 16 Mexican plaintiffs charged that the plaintiffs were assaulted, threatened, and held at gunpoint by Barnett and members of his family.

After Roll's ruling and prompted by several talk-radio programs, he was the subject of hundreds of complaining phone calls and death threats and he and his family were under the protection of the U.S.

[16] Roll was shot on January 8, 2011, outside a Safeway supermarket in Casas Adobes, Arizona,[17] when Jared Lee Loughner opened fire at a "Congress on Your Corner" event held by Democratic U.S. Representative Gabby Giffords.

[2] Chief Justice John Roberts issued a statement, memorializing Roll as "a wise jurist who selflessly served Arizona and the nation with great distinction, as attorney and judge, for more than 35 years", adding "his death is a somber reminder of the importance of the rule of law and the sacrifices of those who work to secure it".

[23] Other plaudits came from Senator John McCain, who had recommended Roll for appointment to the federal bench; from Pima County Sheriff Clarence Dupnik; and from Bishop Gerald Kicanas of the Roman Catholic Diocese of Tucson, who noted that Roll was an active parishioner who "lived his faith".

[24] Then-Chief Judge Alex Kozinski of the United States Court of Appeals for the Ninth Circuit, whose jurisdiction included Arizona, stated that "Judge Roll was a widely respected jurist, a strong and able leader of his court, and a kind, courteous and sincere gentleman".

Roll lived in the area, and had attended the event to continue a prior conversation with Giffords about the volume of cases in Arizona Federal courts.