Republicans are publicly howling at the U.S. surveillance panopticon now that it ensnared Donald Trump’s 2016 campaign. But it’s hard to believe they’ll do much to actually constrain it. When they controlled Congress, whatever Trump-prompted hesitancy Republicans had about the government’s broadest and most intrusive activities dissolved when it was time to renew the authorities underlying them for another five years. They joined congressional Democrats in resurrecting those authorities, continuing an act of genuine bipartisanship that ravenously eats away at Americans’ freedom.

Relief may come instead from the courts. A little-noticed ruling earlier this month from a federal appellate court took a modest step toward curbing the FBI’s practice of searching—warrantless—for Americans’ data inside the National Security Agency’s dragnets ostensibly aimed at foreigners. Congress may be disinclined to close what’s known as the “backdoor search provision,” but there’s a renewed chance the courts might.

In September 2011, authorities arrested Albanian citizen and Brooklyn resident Agron Hasbajrami at Kennedy Airport. Hasbajrami had a one-way ticket to Turkey and, prosecutors said, a plan to continue on to Pakistan to pursue jihad. Facing federal charges, Hasbajrami asked prosecutors if evidence against him derived from warrantless surveillance. In secret, they had collected Hasbajrami’s emails through surveillance resulting from Section 702 of the Foreign Intelligence Surveillance Act (FISA), which permits the NSA to collect massive amounts of internet communications and associated data, including from Americans’ international conversations, all without judicial approval or individual suspicion. Once obtained, the feds applied for a FISA warrant on Hasbajrami, thereby laundering their illicit surveillance for use in prosecuting him.

The government, following a practice of not revealing how such surveillance impacts criminal prosecutions, deceitfully neglected to tell Hasbajrami how they got his emails in the first place. As a result, Hasbajrami pleaded guilty in 2012 and began serving a 16-year sentence for material support to terrorism.

But after the 2013 revelations of mass surveillance Edward Snowden provided to The Guardian and The Washington Post, the Justice Department revealed to Hasbajrami that it had lied to him. Hasbajrami argued that he had been denied critical information underlying his decision to plead guilty—as well as a shot at arguing his prosecution was unconstitutional—withdrew his plea, and sought to suppress the ill-gotten evidence.

The case made its way to the Second Circuit Court of Appeals, which issued its ruling on Dec. 18. Judges in the case did not deal anything close to a death blow to Section 702. But, in a first for a federal appellate court, the judges found that warrantlessly searching through the NSA’s Section 702 databases, as the FBI and the CIA are permitted to do, “could violate the Fourth Amendment, and thus require the suppression of evidence.” Considering themselves without sufficient information to rule on the merits, they instructed the district court to investigate whether “such querying was reasonable.”

That’s a far cry from stopping either the NSA’s warrantless mass collection of internet data or the FBI’s warrantless searches of what the NSA collects. It’s uncertain what the district court will ascertain. But the appellate-court ruling is a step toward judicially mandated constraints on, at least, the downstream effects of such surveillance, and those effects include locking people up, so civil libertarians took what they could get. “Critically, the court holds that the government does not have carte blanche to amass Americans’ emails and phone calls and search through them at will,” noted the ACLU’s Patrick Toomey, who submitted a brief in the case.

The ruling comes after the secret spy panel known as the FISA Court ruled that the FBI’s use of the backdoor search provision is overbroad, abusive and illegal. On one single day in December 2017, according to the court, the FBI conducted 6,800 searches through NSA databases of ostensibly foreign information using Americans’ Social Security numbers. More broadly, the FBI’s searches, the court found, were not “reasonably designed” to find evidence of crime, but were instead fishing expeditions. The total number of Americans surveilled remains unknown.

The revelation that the FBI abused the backdoor-search provision made no political impact, as it concerned millions of Americans not named Donald Trump and its major effects will be felt by Muslims. Along with the Hasbajrami ruling, it highlights how the erosion of Americans’ privacy, at scale, occurs with vastly fewer safeguards than the process to surveil Carter Page, a Trump campaign foreign-policy adviser who had been proximate to Russian intelligence for years.

The FBI had to detail for the FISA Court why it believed Page was a legitimate target for foreign-agent surveillance and do so every 90 days for as long as it wished the surveillance to continue. In practice, Justice Department inspector general Michael Horowitz found, the applications to the FISA Court on Page contained material flaws, such as the omission of evidence that undercut the government’s basis for the surveillance. As egregious as the FBI’s manipulation of that process was in Page’s case, no such process applies for surveillance under Section 702, which affects orders of magnitude more people.

The director of national intelligence and the attorney general merely submit annual guidelines to the FISA Court purporting to describe how the mass surveillance will unfold. The government needs neither probable cause nor reasonable suspicion that any of the millions of people caught in the NSA dragnet committed any wrongdoing—only confidence that the supposed “target” of the surveillance is reasonably believed to be a foreigner overseas. Nor does the FBI require any judicial approval for any of its searches for Americans’ data in the NSA digital storehouses. The appellate court in the Hasbajrami case called it “programmatic pre-clearance” for surveillance on a scale unthinkable even a generation ago.

This sort of surveillance has proven a fixture of contemporary American life, however undetected it typically goes. Attempts at modifying it or abolishing it, launched by the civil-libertarian minorities of both parties, typically fall short. A recent effort at abolishing a highly abused domestic phone-data surveillance program wrapped into the PATRIOT Act was obviated by a Congressional budget deal that kept that and three other expiring PATRIOT provisions alive until March.

One of the few consistent congressional opponents of overbroad surveillance is Sen. Ron Wyden, an Oregon Democrat on the intelligence committee who has fought the backdoor-search provision since its inception.

“I’m glad some of my pro-surveillance colleagues are now interested in protecting Americans against unnecessary government surveillance. But anyone who has concerns about warrants overseen by a judge should be far more worried by backdoor searches of vast numbers of Americans’ communications—searches performed without any court order whatsoever,” Wyden told The Daily Beast. “When Sen. [Rand] Paul and I tried to reform this program last year, these same members voted against even modest reforms to protect Americans’ rights. Let’s be sure that protecting civil liberties applies to all Americans, not just Donald Trump and his cronies.”