The Seventh Circuit has rejected a challenge to a reinstatement.  The petitioner argued that he did not "illegally" reenter the United States after deportation because he was waved into the United States, a situation recognized by the Board of Immigration Appeals as a procedurally regular entry.  The court disagreed, finding that the petitioner's substantive illegal (albeit procedurally regular) entry still triggered the reinstatement provision.  

The full text of Macias Mendoza v. Sessions can be found here: