The first is the preemption argument. The administrator argued that the discretion granted to him to elect portability under the terms of 26 U.S.C.A. 2010 trumped Oklahoma law concerning the fiduciary obligations owed by estate administrators to potential beneficiaries of the estate. The Oklahoma Supreme Court found that because the federal statute was silent as to the effect state laws might have on how the administrator must make the portability election, state law essentially fills in the gap. Thus, absent an expressed Congressional purpose served by the DSUE election choice, state fiduciary law could restrict that choice, as it did here.