He didn’t pass it through Congress, even though he had overwhelming majorities for almost two years, because there were not enough votes. He also didn’t do it by regulation, because that would take time and be subject to public comment and other messy procedures.
Instead, Obama simply has issued an internal policy not to deport illegal aliens other than those who have committed some other serious crime.
Janet Napolitano tried to justify the change based on the need to focus on violent criminals and couched the change in the language of prosecutorial discretion. Those excuses were flat out pretexts; each of the justifications has existed for years. This is simply part of Obama’s 2012 campaign, as he hopes to gain votes in states with large Hispanic populations.
This was no mere internal operating procedure or prosecutorial discretion. This was a political decision which came only when the political process had failed to produce the results Obama wanted. Even if you support the substance of the decision, it should worry you that we have a President with such a low regard for the political process.
I have often warned that what Obama could not achieve through legislation, he would achieve through regulation. Now the corollary: What Obama cannot achieve through legislation or regulation, he simply will do anyway.