Most judges who have ruled on this issue, including some Democratic appointees, have found that the regulation does violate the law.
Last summer, Obama directed immigration agencies not to deport some illegal immigrants who were brought to America as children, and to give them work-authorization permits. In effect, he implemented much of the DREAM Act that Congress has long debated, but never enacted.
Defenders of this action said he was merely prioritizing scarce law-enforcement resources, but that excuse won't wash: It would mean that a future Republican president could announce, for example, that he isn't going to burden the bureaucracy with collecting capital-gains taxes.
Even if Obama were right about these policies - and I'm sympathetic to the goal of the DREAM Act - he went about them the wrong way, disregarding laws he swore to execute.
Complaints about Republican obstructionism are no excuse. Even if Republicans are behaving badly, they have at least acted lawfully in opposing the president.
Obama is not, of course, the first president to flout the law. His supporters will surely respond to this litany by repeating the charge that President George W. Bush "shredded" the Constitution.
The Bush administration claimed that the Constitution gave the president powers as commander-in-chief, trumping laws that tried to restrict his ability to protect national security. It was a debatable, but not frivolous, argument.
Obama is making no similar constitutional claim, and his defiance of constraints on his power isn't confined to one area of policy. Again and again, he has imposed liberal policy preferences rather than follow the law.
In 2011, Obama was asked why he hadn't imposed the DREAM Act unilaterally.
"America is a nation of laws, which means I, as the president, am obligated to enforce the law," he responded. "There are enough laws on the books by Congress that are very clear in terms of how we have to enforce our immigration system that for me to simply through executive order ignore those congressional mandates would not conform with my appropriate role as president."
That Obama was right.
The president's routine violation of the law that he is supposed to uphold isn't covered in the media as a scandal. It ought to be.
Ponnuru, a visiting fellow at the American Enterprise Institute and a senior editor at National Review, is a Bloomberg View columnist.