Elliot Williams ( @elliotcwilliams ) is a CNN legal analyst. A principal at the Raben Group, a national public affairs and strategic communications firm, he was formerly a deputy assistant attorney general at the Justice Department, and an assistant director at US Immigration and Customs Enforcement. The views expressed here are the author's. View more opinion on CNN.

(CNN) There's an old Scottish saying, "mony a mickle maks a muckle." (For us non-Scots, that's, "look after the pennies, and the dollars will look after themselves.")

The (latest) Trump administration scandal over Air Force stays at Trump Turnberry, a luxury Scottish golf resort owned by the President, might appear to be just about pennies and dollars: how the government spends its money, and whether that money ought to line the President's pockets.

But more importantly, in Turnberry we see yet another example of an administration with an unprecedented level of contempt for Congress and its constitutional duty to oversee the executive branch. It's a serious and open question whether the administration's flagrant stonewalling of Congress is an anomaly that will correct itself once Trump leaves office or if, sadly, we now have a new model for how our government works. This question grows even more troubling when the administration's institutional disrespect for Congress is fueling the President's personal self-dealing.

Some context: in June, the House Committee on Oversight and Government Reform sent the Defense Department (which houses the Air Force) a letter with concerns about Turnberry: ballooning US military expenditures at Glasgow Prestwick airport, the debt-ridden airport that serves the resort; Prestwick's offering of discounted rooms to US military personnel; and the President's continued financial stake in his Scotland golf courses (in possible violation of the Emoluments Clause of the US Constitution). Nearly two months later, the Defense Department still has not responded. The committee has now threatened to issue a subpoena for documents.

In fairness, I know well from working on oversight on both sides (on the Senate Judiciary Committee and in the Obama administration), that the processes between the executive and legislative branches can take time. Still, we should be wary here. From the first days that Trump misled the American people that any investigation of his administration would constitute " presidential harassment ," his administration has consistently made witnesses unavailable to testify and ignored oversight requests. For instance, one of the most basic ways in which Congress does its work is through requests for documents, most of which are negotiated with little fanfare. However, in a display of arrogance that would have been unheard of in any prior administration, the current administration has, on at least 30 occasions , refused or delayed turning documents over to Congress.

They have been no more forthcoming with providing live testimony. In a baffling exchange earlier this year, Treasury Secretary Steven Mnuchin complained (some might say whined) to the chairwoman of the House Financial Services Committee -- a body that plays a big role in whether his job exists in the first place -- that his testimony was making him late to an "important meeting." At least he showed up. Commerce Secretary Wilbur Ross blew off his Department's annual budget hearing, an event highly unlikely to feature partisan fireworks. The committee's chair could only call Ross's action a " stunning disrespect " of Congress. The Trump administration even recently made the absurd argument in court that Congress doesn't even have the power to enforce its own subpoenas, and can only ask the executive branch to do so.

Which brings us to Turnberry. We should commend the Air Force for opening a probe into how it chooses hotels. But this step fails to address questions that only congressional oversight and investigation can. A number of the documents the committee has requested go right to whether the Defense Department, as part of the executive branch, has spent its money wisely. Such an inquiry is a core function of congressional oversight, and the Air Force ought to turn that body of documents over immediately.

Second, even setting aside the basic pennies-and-dollars aspect of Turnberry, the matter raises serious constitutional questions about the President's enrichment while in office. The situation looks even worse in light of the Vice President's staying at a Trump property, the attorney general's plans to host a holiday party at a Trump hotel and the President's desire to host the upcoming G7 summit at another of his resorts. It is a widely-held view today that Congress is the only body with the authority to hold a president accountable for violations of the presidential oath of office to uphold the Constitution.

Regardless of whether an investigation leads to impeachment, it would be an act of malpractice for Congress not to gather as much information as possible. And that may have just gotten much easier. Despite disagreement within their ranks over what to call it , a panel in the House of Representatives quietly took a step on Thursday toward impeaching the President, by approving a series of rule changes that would make an impeachment possible. Any evidence gathered in connection with an investigation into Turnberry could be presented in an impeachment proceeding.

JUST WATCHED House Dems move forward with impeachment probe Replay More Videos ... MUST WATCH House Dems move forward with impeachment probe 02:05

All of this makes the administration's slow-walking deeply concerning. Of course, true to the administration's slow-walking playbook, the Defense Department has not given Congress any indication as to when to expect a response. This delay, coupled with new internal restrictions on how the Defense Department provides information to Congress, suggests that nothing will be different this time. We even have already seen an all-caps tweet from the President, proclaiming unconvincingly that Turnberry has "NOTHING TO DO WITH ME." If history is any guide, anyone playing Trump congressional oversight bingo will only need "President tweets irrelevant backtrack of prior tweet" (likely text: "I NEVER SAID I didn't suggest Turnberry was a great place to stay!!!") to complete her board. It's just a matter of time.

Regardless of what the current administration thinks, Congress is a coequal branch of government. (See, e.g., Rock, Schoolhouse , for further background.) Each day that passes without full cooperation from the administration is another in which we get closer to a permanent world in which the executive branch no longer regards Congress as an equal. And simply put, this violation of basic norms of government is making it impossible for Congress to do its job. Congress is unable to determine whether the President has broken the law -- whatever the outcome might be. Congress has a right to be furious, and ought to act swiftly.

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Get on it, Congress. Or, as they'd say across the pond, "Heid doon, arse up."