and harassment by Naval and Marine Corps officers in Las Vegas, Nevada. Subsequent to this investigation, and at the direction of the chairman of the US Senate Armed Services Committee, Senator Sam Nunn, the Naval Investigative Service was restructured into the Naval Criminal Investigative Service (NCIS). The restructuring occurred as a result of perceived lapses in proper investigative technique over the Tailhook scandal, as well as chain of command issues and a lack of civilian oversight in previous investigations. At the time, Senator Nunn stated, "The Navy's whole investigative technique should be under serious question." As a result of the investigation into the Tailhook scandal, the Pentagon's inspector general was sharply critical of NIS leadership, stating that there was a top-down culture showing a lack of cooperation with other authorities in the Navy. By 1992, Acting Secretary of the Navy, Sean O'Keefe, recommended the word "Criminal" be included in NIS's name in order to make clear their investigative function. Ultimately, NIS commander, Rear Adm. Duvall Williams Jr., was forced to retire and NIS was reorganized as NCIS under civilian leadership. Recent history In 1993, the NCIS mission was again clarified and became a mostly civilian agency. Roy D. Nedrow, a former United States Secret Service (USSS) executive, was appointed as the first civilian director and the name changed from Naval Investigative Service Command to Naval Criminal Investigative Service (NCIS). NCIS was aligned as an echelon two activity under the Secretary of the Navy, via the General Counsel. Nedrow oversaw the restructuring of NCIS into a Federal law enforcement agency with 14 field offices controlling field operations in 140 locations worldwide. In 1995, NCIS introduced the Cold Case Homicide Unit, the first dedicated federal-level cold case homicide unit. The unit has resolved 61 cases since 1995. In May 1997, David L. Brant was appointed director of NCIS by Secretary of the Navy John Howard Dalton. Director Brant retired in December 2005. He was succeeded by Director Thomas A. Betro, who was appointed director of NCIS in January 2006, by Secretary of the Navy Donald C. Winter. Betro retired in September 2009. On September 13, 2009, deputy director of operations Gregory A. Scovel was appointed acting director by Under Secretary of the Navy Robert Work. He served concurrently as deputy director for operations until the new director was selected. In 1999, NCIS and the Marine Corps Criminal Investigation Division (USMC CID) signed