Sitting US Congresswoman Gabby Giffords is shot in the head along with 18 others in a mass shooting in Tucson, Arizona. Giffords survived the assassination attempt, but six others died, including John Roll, a federal judge.

Gabrielle Dee Giffords is an American retired politician and gun violence prevention advocate. She served as a member of the United States House of Representatives representing Arizona's 8th congressional district from January 2007 until January 2012, when she resigned due to a severe brain injury suffered during an assassination attempt. A member of the Democratic Party, she was the third woman in Arizona's history to be elected to the U.S. Congress.

On January 8, 2011, United States Representative Gabby Giffords and 18 others were shot during a constituent meeting held in a supermarket parking lot in Casas Adobes, Arizona, in the Tucson metropolitan area. Six people were killed, including federal District Court Chief Judge John Roll; Gabe Zimmerman, one of Giffords's staffers; and a nine-year-old girl, Christina-Taylor Green. Giffords was holding a meeting called "Congress on Your Corner" in the parking lot of a Safeway store when Jared Lee Loughner drew a pistol and shot her through the head at point-blank range before proceeding to fire on others. One additional person was injured in the immediate aftermath of the shooting. News reports identified the target of the attack to be Giffords, a Democrat representing Arizona's 8th congressional district. Giffords's medical condition was initially described as "critical".

John McCarthy Roll was a United States district judge who served on the United States District Court for the District of Arizona from 1991 until his murder in 2011, and as chief judge of that court from 2006 to 2011. With degrees from the University of Arizona College of Law and University of Virginia School of Law, Roll began his career as a court bailiff in Arizona and became an assistant city attorney of Tucson, Arizona in 1973. Later that year, Roll became a deputy county attorney for Pima County, Arizona until 1980, when he began serving as an Assistant United States Attorney for seven years. President George H. W. Bush appointed Roll to a federal judge seat in Arizona after Roll served four years as a state judge.