summary of u.s. suit against arizona's interference with immigration policy

Nerissa at The Opportunity Agenda has a good, brief summary of the complaint:

1. The Arizona law, as a whole, is invalid because it sets forth a state-level immigration policy that interferes with the federal government's preeminent authority to administer and enforce immigration laws; and

2. Sections 2-6 of the Arizona law are invalid because each section either conflicts with, or undermines, established Congressional objectives, federal enforcement and policy priorities, and/or existing federal laws and Constitutional principles.

Basically, Supremacy Clause, fools. What was AZ thinking?