Former U.S. Rep. Gabrielle Giffords is among those who will help dedicate a new federal courthouse named after the judge who was killed in the 2011 shooting rampage in Tucson.

Americans for Responsible Solutions, the group Giffords founded with her husband, announced she will speak about John Roll at Thursday afternoon's ceremony in Yuma.

U.S. Senators John McCain and Jeff Flake, as well as three of Arizona's congressional representatives, are also expected to attend.

Roll was one of six people killed in the January 2011 mass shooting. Giffords and 12 others were wounded.

Roll, who served as chief federal judge in Arizona, signed off on the design of the new courthouse days before his death.

The $25 million courthouse includes two courtrooms, judges' chambers and other court-related offices.