From what I've read on the matter, there was some speculation as to the possibility of Hillary Clinton being put somewhere in the cabinet in the early Clinton years, likely at Attorney General, citing her own law career. Besides the obvious questions of nepotism that plagued JFK when he put his brother at the helm in 1961, what could this mean, if it goes ahead, for Bill Clinton in the early 1990s?
Was this ever anything more than idle DC Villager speculation in early '93?
I remember as a precocious youth reading a suggestion that Jimmy Carter could be Clinton's secretary of state, which now seems ridiculous, but was obviously written at a time when it looked like Bubba would govern as a continuum of the Cold War liberals--and some people were smart enough to perceive that Carter not only had diplomatic chops (Camp David) but was untainted by any foreign policy corruption scandals, unlike the Reaganites and the Bushies. But it wouldn't have worked.
But Hilary as AG? Apart from the federal law that chris N mentions, there's the fact that she hadn't worked fulltime in government service since the seventies (in a junior position), while RFK was a Capitol Hill committee staffer in the years immediately before Camelot (and a high profile one at that.)
Hilary in 1993 is probably as unqualified to lead the Department of Justice as Mitchell was in '69. And John Mitchell avoided any damaging criticism of his lack of public service qualifications because, well, it's not as if he entered office in the post-Watergate era of good governance reforms.