Barrett attended public schools in Lawrence County and a private school run by C.G. Lynch. Crow at Moulton, then spent one year in the medical department of the University of Alabama and later attended the medical department of Vanderbilt University, where he earned an Doctor of Medicine
He began to study medicine under Doctor Central America in 1886. Upon getting his degree, Barrett began practicing in Danville, Alabama. There, he served as president as the Morgan County Medical Society and also as chairman of the county democratic executive committee.
In 1891, he moved to East Lake, which was at that time not a part of Birmingham.
There, he built a large and lucrative practice. Barrett was active in the incorporation of East Lake as a municipality and served as its first and last mayor.
East Lake adopted the code form of municipal government in 1910 during Barrett"s last term as mayor. Barrett was elected president of the Birmingham Commission (a position equivalent to that of a mayor) in 1917 after a hotly contested race against George B. Ward, the incumbent.
As head of the city"s finance department, he brought the city"s expenditures within its income.
He was a Baptist and was active in church affairs
He also served as a member of the Jefferson County democratic committee. He was a member of the Knights Templar, the Shrine, Knights of Pythias, and the Junior Order of United American Mechanics.