You can try the Bureau of Prisons at:www.BPO.gov
They have some records depending on the institution. They go back at least 30 years and before that you can get some info but not all as most records, other than name and brief info, are not kept after 30 years.
I just found my father in the 1940 census in prison in Missouri he had told us kids a little bit but I am finding that the whole truth was not told. It is not bad but it was just something they never talked about. The old skeleton in a closet thing. Anyway good luck in your search and hope this helps.