in 1946, ennis did resign from the department of justice, and joined the board of the aclu himself. he became the aclu's general counsel in 1955, and was elected chairman of the aclu in 1969, succeeding ernest angell who was retiring after 19 years with the organization. he served as aclu president until 1976, during which time he called for the resignation of president richard nixon and an end to the property tax exemption enjoyed by religious organizations. notwithstanding the former, he was critical of the zealousness of opposition to nixon shown by charles morgan, jr. of the aclu's washington, d.c. office. he was succeeded as aclu president by norman dorsen. he remained a member of the aclu executive committee until 1985.