Osro Cobb earned two bachelor's degrees from Henderson State University in 1925 and was admitted to practice law before the Arkansas Supreme Court in 1929. He began his legal career with the Campbell, Mallory, and Throgmorton law firm in Little Rock and later formed the Cobb, Cazort, and Holt law firm. Cobb held leadership roles in the Arkansas Republican Party and ran for governor in 1936. He served as a judge advocate in the United States Army Air Corps and was elected US attorney for the Eastern District of Arkansas in 1954, where he played a role in the desegregation of Central High School. Appointed to the Arkansas Supreme Court in 1966, Cobb represented the US government in a federal case against Governor Faubus.

Osro Cobb's political philosophy is marked by an intriguing blend of Republican principles and unexpected alliances, particularly in his advocacy for minority party representation and desegregation. His strategic approach often juxtaposes traditional economic conservatism with progressive civil rights actions, as seen in his support for Initiated Act 3 and his role in desegregating Central High School. Cobb's rhetoric frequently emphasizes personal integrity and public service, yet his policy stances reveal a calculated pragmatism in balancing regional industrial interests with broader social reforms.