Can the US Supreme Court hear an appeal from State Supreme Court w/o a federal question?

Is it a matter of choice that the US Supreme Court will reject a case from a State Supreme Court that does not have a federal question or are there binding jurisdictional requirements that would prevent them as well? I understand the point about their inability to reinterpret state law already interpreted by state courts.

Also, if a case reaches a State Supreme Court and the parties are not diverse and there is no federal question in the suit, is that the end of the road?

Do US federal agencies take a position on legislation?

  1. Are there laws which prohibit or limit the ability of United States federal agencies (eg. SAMHSA) to take a public position in favor or against bills currently under consideration of the legislature?
  2. Under what circumstances do agencies typically take positions? On what basis do they decide to take a position or not?