Frankly, I don't know that I WANT somebody with a clean background check in the FBI. Some of the best cops I know are good cops because they pulled all kinds of stunts when they were teenagers and know the tricks that punks pull.
If they want to hire former mobsters for the FBI, that's fine with me as long as they are pro-American mobsters. So far the FBI strikes me as being FAR too "white collar" in character to do the dirty work they are expected to do.