In his early career, he served as a lawyer in the Franklin D. Roosevelt administration and a clerk to Supreme Court justices Benjamin N. Cardozo and Felix Frankfurter.

[2][1] Rauh worked with Ben Cohen and Tom Corcoran, both from President Franklin Delano Roosevelt's Brain Trust, writing New Deal legislation,[1] before clerking at the Supreme Court, with Justices Benjamin N. Cardozo and Felix Frankfurter.

[1][3] after working as the Deputy Counsel for both the Lend-Lease Administration and the Office of Emergency Management,[1] He and Phil Graham, later the Washington Post publisher, tried to enlist in the Army Air Corps the day after Pearl Harbor.

He was general counsel for labor leader Walter Reuther and the United Auto Workers, handling much of the UAW's civil liberties policy.

Starting as a Democratic National Convention delegate in July 1948, he was a leader that year in writing up the civil rights plank for Humphrey.

In the letter of support promoting his award of the Presidential Medal of Freedom, its authors described the plank as "the foundation for all of the human rights and equal protection laws that have since been enacted.

"[4] On September 12, 1948 (a Sunday) at 8:30 PM, Elizabeth Bentley appeared again on the first-ever television broadcast via WNBT of NBC's Meet the Press and was the first interviewed.