jig·ger·y-pok·er·y (jĭg'ə-rē-pō'kə-rē) n. Underhand scheming or behavior: "By some legal—or perhaps illegal—jiggery-pokery, he could declare the election void"(John Hughes).
[Alteration of joukery-pawkery : from Scots jouk, to dodge (probably from duck2) + Scots pawk, trick.]