Makes sense, T'Girl. Keiko was unattached and serving aboard a Starfleet vessel without being a member of Starfleet. So it seems that Starfleet does employ civilians as consultants or experts in some fashion.
Afterall, while Starfleet science officers have shown quite a depth of knowledge in a variety of subjects, they can't be experts in all of them. An in-depth expert on say, botany, would be of value to a ship that will encounter strange new plants on a regular basis, while at the same time needing an arboretum tended to, both for it's recreational possibilities as well as its educational and research purposes.
So, perhaps the Saratoga employed Jennifer Sisko as a consultant, too. Her mirror counterpart was a scientist, so perhaps our prime universe Jennifer was, too.
Afterall, while Starfleet science officers have shown quite a depth of knowledge in a variety of subjects, they can't be experts in all of them. An in-depth expert on say, botany, would be of value to a ship that will encounter strange new plants on a regular basis, while at the same time needing an arboretum tended to, both for it's recreational possibilities as well as its educational and research purposes.
So, perhaps the Saratoga employed Jennifer Sisko as a consultant, too. Her mirror counterpart was a scientist, so perhaps our prime universe Jennifer was, too.