This could get interesting

In an interesting development regarding Emperor Barry's exercise of "executive authority" in rewriting immigration law without the benefit of actual legislation, The Volokh Conspiracy is reporting (hat tips to Insty and Ace) that a federal district court in Pennsylvania has ruled that the emperor's decision to stop deporting pretty much all illegals, while granting work permits to many of them, is unconstitutional:

According to the opinion by Judge Arthur Schwab, the president’s policy goes “beyond prosecutorial discretion” in that it provides a relatively rigid framework for considering applications for deferred action, thus obviating any meaningful case-by-case determination as prosecutorial discretion requires, and provides substantive rights to applicable individuals. As a consequence, Schwab concluded, the action exceeds the scope of executive authority.
This is the first judicial opinion to address Obama’s decision to expand deferred action for some individuals unlawfully present in the United States. [I've now posted the opinion here.]

The question arose in a deportation case involving an illegal immigrant who was deported and re-entered the country illegally. The judge asked the parties to brief the applicability of the emperor's amnesty, then ruled that amnesty to be an unconstitutional attempt to expand executive authority. While this case might end up being important, it might not. But I think we can expect to see a lot of litigation over this issue.