DACA was instituted before DAPA, but you are correct; they have the same philosophy and justification. DACA was challenged in Johnson v. Crane, but in that case the 5th Circuit held Mississippi did not establish standing, so the constitutionality of DACA was never ruled on its merits.
The challenge to DAPA also went as far as the 5th Circuit, but was found unconstitutional in U. S. v. Texas. That decision is still law as SCOTUS was tied 4-4.
I rarely say a case like this is a slam-dunk at SCOTUS but this one should be. The whole basis of the 0bama regime justification of DAPA in U. S. v. Texas was that DAPA was an exercise of prosecutorial discretion. It was an executive decision to defer prosecution under certain guidelines. The reason that the regime had to posture the argument in that way is that if the DAPA policy created a class of persons lawfully present in the United States, the government loses. Everyone conceded the executive does not have authority to create a class of persons lawfully present. Only Congress can do that.
The flip side of that coin, as we see in this case, is that prosecutorial discretion does not create any substantive or procedural right on the person who benefits from it. The executive has full authority to grant it and the decision is not reviewable by a court. But then again, so is the decision to take it away. Another aspect of prosecutorial discretion is that it does not have to go through the notice and comment procedure for executive rulemaking. DAPA and DACA did not go through that administrative process when they were created.
In the present case, the District Court recognized a procedural right of due process before the rule is rescinded, and also found the Trump administration did not go through the notice and comment procedure. That may win the battle, but it loses the war. Once the plaintiffs argue that there is a due process right and a notice and comment requirement, they have admitted that the DACA policy is Executive rule-making, and creates a class of persons lawfully present.
That, everyone concedes, the Executive cannot do. Therefore, DACA is doomed based on the posture the plaintiffs have taken.
“In the present case, the District Court recognized a procedural right of due process before the rule is rescinded, and also found the Trump administration did not go through the notice and comment procedure.”
I suppose that’s a good point, although what sort of notice and comment procedure did Obama entertain prior to the EO?
Trump did not simply pull the plug, there was ample time given for congress to remedy the situation and there’s been plenty of ‘comment’ in both houses. In addition, seems like due process is built in since each approved application is only for a two year period. If I understand correctly, ending the program simply meant these applications would no longer be accepted for renewal. As the name implies it’s only Deferred.