Well Tarkin?
Federal juries in California use California residents as jurors.
Read a book.
"Article III, Sec. 2 requires that federal criminal cases be tried by jury in the State and district in which the offense was committed, but much criticism arose over the absence of any guarantee that the jury be drawn from the ''vicinage'' or neighborhood of the crime. Madison's efforts to write into the Bill of Rights an express vicinage provision were rebuffed by the Senate, and the present language was adopted as a compromise. The provisions limit the Federal Government only."
http://caselaw.lp.findlaw.com/data/constitution/amendment06/