The Justice Department will ask a federal judge to block Arizona’s SB 1070 from taking effect this afternoon. Julianne Hing will be keeping up with [District Judge Susan Bolton’s deliberations](/archives/2010/07/sb_1070_injunction_hearing_today_1.html). But for a refresher on the broader legal debate, revisit [Daisy Hernandez’s breakdown](/archives/2010/07/is_sb1070_unconstitutional.html) of the arguments both sides will be making about the law’s constitutionality. There’s more nuance than there may seem to be and the ruling’s not likely to be a clean one.