On May 3, 1970, the day before he took his oath of office as mayor, Landrieu received a death threat by telephone, but authorities quickly caught the culprit. During his tenure as mayor, Landrieu oversaw desegregation of city government and public facilities as well as encouraging integration within business and professional organizations. Before Landrieu was elected, there were no high-ranking black employees or officials in City Hall; he worked actively to change this by appointing African Americans to top positions, including Chief Administrative Officer, the number two position in the executive branch of city government. When Landrieu took office in 1970, African Americans made up 19 percent of city employees; by 1978, this number had risen to 43 percent. He also appointed Reverend A.L. Davis to fill a temporary vacancy on the City Council; Davis was the city's first black city councilor. Landrieu also employed an African American assistant: Robert H. Tucker, Jr.