Well, it may not be unconstitutional. Or maybe it just has to be read in context of some piping hot case law and a side of Georgia's home-baked Article 3 analysis (yes, it's almost dinnertime, and I have supper on the mind, as you can tell).
OK, gather `round, grab a pillow in case you doze off, and let's jump right in.
First, as KagroX and others pointed out on that thread, the key phrase in HR 418 is "not withstanding any other provision of law..." As KagroX pointed out, that's the bullshit factor. It's incorporated as boilerplate language in many bills. Thus, decoding legislative speak, this:
So that phrase should be a red flag of sorts, not a major one though, that someone somewhere in some tiny basement office in the Capitol knows they're reaching on this one.
No Review? No way!
Yes, way. Congress has incredible power when it comes to limiting (or creating) the jurisdiction of the federal courts. As background, let's look at Article III of the United States Constitution. Does everyone have a copy or should I pass one out? (wow, the Constitution is still available to the public! I guess George hasn't gotten `round to censoring the internets yet.)
Here is the relevant section we'll be working with the judge the constitutionality of HR 418:
Section 2. The judicial Power shall extend to all Cases, in Law and Equity, arising under this Constitution, the Laws of the United Stats, and Treaties made, or which shall be made, under their Authority [...]; --to Controversies to which the United States shall be a Party [....]
In all cases affecting Ambassadors, other public Ministers and Consuls, and those in which a State shall be a Party, the supreme Court shall have original Jurisdiction. In all the other Cases before mentioned, the supreme Court shall have appellate Jurisdiction, both as to Law and Fact, with such Exceptions, and under such Regulations as the Congress shall make.
The first thing we should be readily cognizant of is that lower federal courts are a creature of statute, specifically, the Judiciary Act of 1789. It was then that Congress said, hey, might as well set up some lower federal courts! So Congress created the district and appellate courts in the federal system, and gave them jurisdiction. But what Congress giveth, Congress can taketh away?
In a word: Yes. Congress can limit the jurisdiction of the federal courts, including the Supreme Court. This is because of the "with such Exceptions, and under such Regulations as the Congress shall make" language of Art. III, Sec. 2. Most of the time, the limit is because Congress prefers the given claim to be adjudicated in a state court. Preclusion of federal jurisdiction while still leaving open state jurisdiction is, if I read the statute correctly, an issue here, because it appears by the plain text of the bill that both federal and state review are prohibited. But can Congress preclude all judicial review, both state and federal, as it appears to be the case here?
Let's check out the precedent for this, shall we?
The Portal-to-Portal Act of 1947 : "No court of the United States, of any State...or of the District of Columbia, shall have jurisdiction of any action or proceeding...to enforce liability or impose punishment [for an employer's falure to pay minimum wage or overtime]."
The statue was challenged, and in Battaglia v. General Motors Corp. (2d Cir. 1948) Judge Chase wrote:
Due Process is encompassed under the 5th Amendment. But we want Article III analysis, dammit! The problem is, the Supreme Court has never squarly been faced with the question of whether Congress could prohibit BOTH federal & state jurisdiction for constitutional matters.
But lookey here, we have some pretty good hints that HR 418 cannot preclude constitutional claims:
Webster v. Doe, 486 U.S. 592 (1988): The Supreme Court ruled that Congress could preclude non-constitutional claims in that case, but that Congress did not demonstrate its intent to preclude constitutional claims. Such preclusion, the Court wrote, demands a "heightened showing" of intent to deny review of constitutional challenges. The Court has been extremely cautious in this area of law, classifying the preclusion of review of constitutional matters as a "serious constitutional question."
More cases! More cases!
Bowen v. Michigan Academy of Family Physicians (1986): The Court found that Congress did not intend to bar constitutional challenges in that case.
Johnson v. Robison (1974): The Court held that a law making determinations of Vet's benefits "final" and "nonreviewable" did NOT apply to constitutional challenges to the validity of the classification. The Court wrote that such preclusion would "raise serious questions concerning the constitutionality of the provision barring judicial review."
The key then, in evaluating HR 418, is to remember that the Constitution is the Supreme Law of the land--not what Congress passes, not what 125 Republican co-sponsors think should be the law.
In Sheldon v. Sill, Justice Story (big shot Supreme Court Justice, for all you non-law folks) wrote that a statute limiting jurisdiction (which is essentially what a statute precluding review does) "cannot be in conflict with the Constitution."
There are limits to Congressional power over jurisdiction and its ability to preclude review; they are at times call "external" restraints because they exist outside of Article III. Namely, these restraints are the Bill of Rights, the rest of the Amendments, and any other Constitutional provision. So no matter how much Rep. Sensenbrenner wants the Secretary to be completely insulated in whatever decision he makes, he's just plain wrong. If the DHS Secretary decides to halt labor laws or take people's property, those are very valid constitutional claims, and could be brought under judicial review.
Still awake? Great. I hope this helped clarify things a bit.