Citing preemption, the Department of Justice reportedly plans to challenge Arizona's law on illegal aliens on the preposterous grounds that it will create too much work for our underperforming federal enforcement agencies. Jerry Markon of the Washington Post reports:

[D]epartment lawyers have been preparing their case, said the sources, who spoke on condition of anonymity because the government has not announced its plans. The filing is expected to include declarations from other U.S. agencies saying that the Arizona law would place a undue burden on their ability to enforce immigration laws nationwide, because Arizona police are expected to refer so many illegal immigrants to federal authorities.