He was a parish priest and high school teacher, diocesan refugee resettlement director, chair of the United Campaign Agency Executives Association, chaplain of Jackson County Jail, and president of the Kansas City Citizens' Alliance for the War on Poverty.
He was appointed executive director of the Campaign for Human Development, United States Catholic Conference, in 1973 and served in that capacity for some five years.
[1] On January 10, 1978, McNamara was appointed the sixth bishop of the Diocese of Grand Island by Pope Paul VI.
[2] He received his episcopal consecration on March 28, 1978, from Archbishop Daniel Sheehan, with Bishops Charles Helmsing and John Sullivan serving as co-consecrators.
[1] In his later years, he served as director of Catholic Relief Services; however, he stepped down in 1997 after African American staff members became outraged by his use of a racial slur.