This U.S. Army file handout photo obtained shows Private First Class Bowe Bergdahl, before his capture by the Taliban in Afghanistan. (AFP/Handout/U.S. Army)

Charlie Savage in the New York Times reports on the about-to-be-released House Armed Services Committee report on the 2014 prisoner swap of five Guantanamo prisoners for captured U.S. soldier/deserter Bowe Bergdahl.

Inevitably, much of the commentary will be about the report’s allegation that President Obama was committed to the swap because getting rid of five high-level Guantanamo detainees would make it easier for him to be able to fulfill his promise to close Guantanamo.

The focus, however, really should be on the blatantly illegality of the prisoner release. In 2014, Congress passed and the president signed a law banning the president from using any Defense Department funds to release prisoners from Guantanamo Bay, Cuba, without giving Congress 30 days’ notice. No such notice was given, apparently because the Defense Department was afraid of a leak that would scuttle the deal.

Let’s take a step back. When I’ve been discussing my new book “Lawless: The Obama Administration’s Unprecedented Assault on the Constitution and the Rule of Law” on talk shows and elsewhere, I inevitably get asked, “Why doesn’t the Republican Congress use its ‘power of the purse’ to cut off funds when the administration is acting or threatens to act illegally?” This, after all, is Congress’s trump card; the Constitution, backed by the Antideficiency Act, clearly bars the president from spending money that Congress hasn’t allocated, even more so when a law explicitly bans the president from spending money. The act forbids federal agencies from spending funds “in excess or in advance of amounts that are legally available.”

So why isn’t the power of the purse a more effective congressional tool? There are several answers to that, including lack of political will by the GOP, a dysfunctional congressional budget process (which the Republicans could, but have not, fixed), increased partisanship that results in one party’s congressional delegation always defending the president at the expense of their own institution’s authority, media coverage that consistently and wrongly frames the issue as Congress ‘shutting down’ agencies (when, in fact, if Congress passes a funding measure and the president vetoes it, from a constitutional perspective clearly he is responsible for any shutdown, as Congress has no obligation to fund anything in particular), and the related fact that most Americans have little idea of how the legislative process works and seem to accept the view that the president “runs” the country.

Another important reason that the power of the purse doesn’t work, however, is that presidents have been undermining it by spending money illegally, no one more so than Obama. Did you know, for example, that Obama not only violated the War Powers Resolution by not getting congressional assent for military action in Libya, but he also never even asked Congress for funding for the war? The Obama administration paid for that conflict entirely out of funds reallocated from other Defense Department accounts. Congress therefore never had an opportunity to decide whether to use the power of the purse to stifle that disastrous intervention. Similar budget tricks have increasingly taken Congress and its wishes out of the equation.

The Bergdahl situation is far less dramatic than Libya from a policy perspective, but even more troubling from a constitutional and rule-of-law perspective. Obama not only spent money he didn’t have, but he also spent money that a federal law explicitly banned him from spending. The nonpartisan Government Accountability Office concluded that the Obama administration violated a “clear and unambiguous law.”

The Obama administration never gave an entirely coherent and consistent explanation for its actions, but ultimately seems to have settled on the rationale that the president’s inherent “commander in chief” powers preclude Congress from micromanaging the disposition of wartime detainees. [UPDATE: This Josh Blackman post reminds me that the administration ricocheted between several dubious rationales, and it’s not at all clear that it settled on the commander-in-chief power). The irony of the present administration adopting John Yoo-like interpretations of executive power should have, but has not, led to a massive backlash from all of his progressive supporters who denounced similar theories when used to promote George W. Bush administration policies.

More important, it’s hard to see how any theory of presidential power can overcome a duly enacted statute banning the president from spending money on something. The president simply does not have any source of funds beyond what Congress allocates, and if Congress explicitly cuts off funding for something, the president has no power to expend government resources on that something.

It almost goes without saying that Democrats will regret the Bergdahl precedent the next time a Republican president is in office, especially if that president chooses to adopt the sort of executive power theories championed in the Bush administration. Regardless of who is in office, though, the Constitution’s checks and balances and the separation of powers will have suffered yet another blow. At some point soon, our system will reach a tipping beyond which it won’t recover.

That’s a heckuva legacy for a president who came into office on this platform: “The biggest problems that we’re facing right now have to do with George Bush trying to bring more and more power into the executive branch and not go through Congress at all. And that’s what I intend to reverse when I’m president.”

UPDATE: Co-blogger Ilya posted about the illegality of the Bergdahl swap last year: “Timothy Sandefur offers a strong critique of the Obama administration’s argument that that provision of the law was unconstitutional. I would add that, in addition to the spending power, this law is authorized by Congress’ Article I power to “make Rules for the Government and Regulation of the land and naval Forces.” The five Taliban prisoners were in military custody at Guantanamo. Regulations governing the treatment and release of prisoners by the military are at the very core of Congress’ power under this clause. When the president acts in his capacity as commander-in-chief of the armed forces, he must obey congressional laws enacted under this power, no less than any other military leader. As liberal Democrats correctly pointed out during the Bush administration, it was illegal for the president to order the use coercive interrogation methods against prisoners in violation of congressionally enacted statutes barring such torture. The same constitutional rule applies here.”

FURTHER UPDATE: Rep. Adam Smith (D-WA), Ranking Member of the House Armed Services Committee, and Rep. Jackie Speier (D-CA), Ranking Member of the Subcommittee on Oversight and Investigations, released a statement today. After noting  “substantial legal controversy over the Bergdahl exchange” the Congressmen assert that “the Administration still should have made a good faith effort to comply with the statute.”