Roll, 64, died of gunshot wounds Saturday outside a Safeway supermarket when a 22-year-old man opened fire on the congresswoman and killed six people and injured 13, The New York Times reported. Roll, who was provided protection by the U.S. Marshals Service after death threats during a 2009 case involving Mexicans suing an Arizona ranches for $32 million, had attended mass at a church nearby right before the shootings.
Chief U.S. Justice John Roberts issued a statement after the shootings, praising Roll for his service.
"We in the judiciary have suffered the terrible loss of one of our own," the statement said. "Judge John Roll was a wise jurist who selflessly served Arizona and the nation with great distinction."
President Barack Obama issued a statement describing Roll as a man "who has served America's legal system for almost 40 years," the Times reported.
Roll was chief judge of the U.S. Court of Appeals for the Ninth Circuit, appointed by President George H.W. Bush in 1991.
He is survived by his wife, Maureen, three sons and five grandchildren.