“The convening of periodic pro forma sessions in which no business is to be conducted does not have the legal effect of interrupting an intrasession recess otherwise long enough to qualify as a ‘Recess of the Senate’ under the Recess Appointments Clause.  In this context, the President therefore has discretion to conclude that the Senate is unavailable to perform its advise-and-consent function and to exercise his power to make recess appointments.” 

That’s how the Department of Justice begins its opinion concluding that the President’s recess appointments were lawful.   We’ll be sharing our thoughts on the opinion soon.