Mr. Barnett, (Southern Methodist University, J.D. 1966, LL.M. 1972) a tax expert who formerly spent a decade with Cox, Castle & Nicholson as their chief tax attorney, was until recently the chair of Sonnenschein’s tax department in Los Angeles. 0 Share: Represented Lisa Hamilton Klein as a partner to Katten, Muchin & Zavis Represented Roger Heyman as a partner to Wickwire Gavin