Robertson then established a private law practice and began his elective career.
He was elected to the Virginia State Senate as a Democrat in 1915 to represent Bedford and Rockbridge counties and Buena Vista, Virginia, in Senate district 22, replacing W. T. Paxton, who had replaced J. Randolph Tucker in 1913.
Robertson served from 1916 to 1922, when he resigned and was replaced by Samuel S. Lambeth Jr. in the February 1923 special session but Robert J. Noell won the election to succeed him later that year.
During World War I, Robertson enlisted and served in the United States Army, but was assigned stateside so he could continue that part-time elective office.

Robertson served as Commonwealth Attorney for Rockbridge County, Virginia (an elective office per the Virginia constitution, which prohibited such officials from also serving as legislators or judges during their terms) from 1922 to 1928.
Robertson then established a private law practice and began his elective career. He was elected to the Virginia State Senate as a Democrat in 1915 to represent Bedford and Rockbridge counties and Buena Vista, Virginia, in Senate district 22, replacing W. T. Paxton, who had replaced J. Randolph Tucker in 1913. Robertson served from 1916 to 1922, when he resigned and was replaced by Samuel S. Lambeth Jr. in the February 1923 special session but Robert J. Noell won the election to succeed him later that year. During World War I, Robertson enlisted and served in the United States Army, but was assigned stateside so he could continue that part-time elective office.
Robertson served as Commonwealth Attorney for Rockbridge County, Virginia (an elective office per the Virginia constitution, which prohibited such officials from also serving as legislators or judges during their terms) from 1922 to 1928.
Absalom Willis Robertson