Jose Luis Gonzalez / Reuters

On Friday, when the Supreme Court temporarily allowed the Trump administration to begin construction of his border wall using up to $2.5 billion in military funds that Congress had denied, President Donald Trump declared a “big victory.” But last week’s order is far from a final ruling. The Supreme Court has not yet decided the ultimate outcome of the case, and no court has given Trump’s abuse of powers the stamp of approval, said that the wall construction is lawful, or suggested that the groups bringing the lawsuit—the Sierra Club and the Southern Border Communities Coalition (SBCC)—do not face real injuries from Trump’s actions. That said, the Court’s order could signal that it is now open to radically cutting back on some of the most basic constitutional safeguards that protect American democracy.

Let’s be clear on what the 5–4 majority actually decided, and the context in which they decided it.

Ever since he announced he was running for office, Trump has claimed that he was going to build a wall. Congress has consistently refused to put taxpayer funds behind that campaign promise. Earlier this year, Trump responded to Congress’s denial of wall funds with the longest government shutdown in U.S. history. For 35 days, ordinary government activities ceased.

Congress held firm, and passed a bipartisan budget that denied any funds to construct a wall outside of Texas. But when Trump signed Congress’s budget into law, he announced that he was going to disregard its limits and take additional billions of dollars from the military for his wall.

Trump’s actions represent an unprecedented power grab. The Constitution is clear that only Congress has the authority to decide how to spend taxpayer funds. The Founders viewed this separation of powers as a key protection against tyranny. As James Madison wrote in The Federalist Papers: “The power over the purse may [be] the most complete and effectual weapon with which any constitution can arm the immediate representatives of the people.”

The Sierra Club and the SBCC then sued to block the wall, enlisting the American Civil Liberties Union, where I work, to take them on as clients. Their members live in, protect, and treasure the lands and communities along the southern border, which are threatened by construction. The administration conceded that these groups have “standing” to sue, which means that they face harm from the government’s actions and have a personal stake in the lawsuit.

Earlier this summer, a district court blocked the administration’s efforts to divert $2.5 billion for the wall—money that Congress originally appropriated for military pay and pensions, chemical-weapons disposal, and support for our allies in Afghanistan. The administration’s argument was that a particular transfer authority, known as Section 8005, gave it the power to redirect these funds.

But Section 8005 is restricted to transfers for “unforeseen military requirements,” and cannot be used to fund an “item” that Congress “denied.” As the district court held, Section 8005 couldn’t possibly apply here: Trump has been asking Congress to pay for a wall for years, and Congress expressly and repeatedly denied that request.

That government appealed the district court’s decision, arguing that the Sierra Club and the SBCC aren’t entitled to judicial review. Even before the appeal was decided, however, the administration asked for an emergency order allowing it to start immediately spending military funds on the wall. When the Ninth Circuit denied its request for an emergency order, the administration asked the Supreme Court to step in.

And it did, issuing a temporary stay. In Friday’s order, a five-justice majority refused to even look at whether Section 8005 applied to Trump’s transfer of taxpayer dollars to the wall. Instead, the majority’s brief, one-paragraph order stated simply that the administration had shown “at this stage” that the Sierra Club and the SBCC could not get judicial review of whether the administration was unlawfully claiming a power under Section 8005. The words at this stage are key. To receive a temporary stay, the bar was lower than for normal court review. The government had to show only a “fair possibility” that it would ultimately prevail. Possibility does not mean eventuality.

But even the Court’s temporary order gives real cause for concern. The administration has been pushing the extreme view that no injured party—not the ACLU’s clients, not affected states, not even the House of Representatives—can go to court to block the president’s blatant abuse of power. Government lawyers have argued in every case challenging wall construction that the president’s actions are effectively unreviewable by the courts. They claim it’s enough for the president to simply say that his actions are authorized by Section 8005, and that no one has the authority to say otherwise.

That is a dangerous proposition, and it would be a huge setback for the American democratic system if the Supreme Court ultimately adopts it. But Trump hasn’t succeeded in persuading five justices to give him that power yet—and for good reason.

Centuries-old precedents empower courts to halt lawless and unconstitutional executive action. As the Supreme Court recognized just four years ago, in a case called Armstrong v. Exceptional Child Center, “The ability to sue to enjoin unconstitutional actions by state and federal officers … reflects a long history of judicial review of illegal executive action, tracing back to England.”

A basic rule of American democracy is that when the government acts without legal authority, the courts are open to injured parties. If the courts close their doors, blatant abuses of power will go unchecked. Everyone in the executive branch, from FBI agents to Cabinet secretaries to the president, would be empowered to disregard the rule of law.

The government told the Supreme Court that if the Sierra Club and the SBCC ultimately win, courts can order that the unlawful wall be taken down. We plan to hold the government to its word, and will seek the removal of every mile of unlawful wall built while this temporary stay is in place.

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