When Texas Attorney General Ken Paxton filed a new lawsuit against the Biden Administration last week challenging the allegedly “unlawful” move to grant asylum officers authority to decide some asylum cases, no one was surprised. It’s the 11th immigration-related lawsuit Paxton has filed against the Administration since President Biden took office.

But the Texas attorney general is hardly alone in his enthusiasm for litigation. Because Congress has failed to act meaningfully since the 1990s to reform the U.S. immigration system, immigration policy has been increasingly shaped by court challenges. In recent years, liberal and conservative attorneys general, nonprofit organizations, and individual plaintiffs have filed an avalanche of immigration-related suits in federal courts, resulting in a profusion of complex and often-contradictory court rulings, experts tell TIME. With Congress on the sidelines, federal judges are now on the frontlines of interpreting and dictating the scope of executive actions, federal guidelines and agency rules—thereby determining how U.S. immigration policy actually works.

“This is a manifestation of our broken immigration system,” Stephen Yale-Loehr, professor of immigration law at Cornell University, tells TIME. Congress’s failure to pass comprehensive immigration reform has resulted in an explosion of agency rules and executive actions—which, in turn, lead to more legal challenges, he says. “Today, almost every executive action on immigration is being challenged in the courts.”

This ad-hoc system has resulted, both at the U.S.-Mexico border and within government agencies, in “peak confusion,” says Theresa Cardinal Brown, managing director of immigration and cross-border policy at the Bipartisan Policy Center (BPC), a Washington think tank. New federal rules or guidances are often blocked, terminated, or forcefully reinstated, sometimes with additional restrictions or requirements, just days or weeks after they were announced. Government officials, immigration lawyers, and lay people are often baffled about the contours of U.S. law, says Elora Mukherjee, professor of law at Columbia University and director of the school’s Immigrants’ Rights Clinic.

Giving judges so much power to determine immigration policy also puts the U.S. judicial system in a delicate spot, Yale-Loehr says. Federal judges are often wary of being drawn into issues of national sovereignty or of ruling in a way that impinges on the executive branch’s authority to conduct foreign policy. But, these days, they often have no choice. “Courts are loath to weigh in,” Yale-Loehr says.

Recently, Supreme Court Justice Stephen Breyer questioned the role of his own court in deciding a case about the Trump-era policy, Migrant Protection Protocols (MPP), which requires the Biden Administration to negotiate with the Mexican government over sending migrants back to Mexico to await asylum hearings. During April 26 oral arguments, Breyer warned his fellow justices to move gingerly. “Foreign affairs is involved,” he said. “And, Judges, this is above your pay grade, okay? Stay out of it as much as you can.”

How did we get here?

Immigration-related litigation has been around for decades, but many experts point to a moment, in 2016, when the floodgates opened.

On June 23, 2016, the Supreme Court voted 4-4 on a case brought by Texas challenging whether a key Obama Administration executive action known as Deferred Action for Parents of Americans and Lawful Permanent Residents (DAPA), could move forward. (Justice Antonin Scalia, who died in February 2016, had yet to be replaced.) DAPA, an expanded version of Deferred Action for Childhood Arrivals (DACA), would have granted some parents of those who arrived unlawfully in the U.S. as children protection from deportation. The tie vote meant the lower court’s decision blocking DAPA remained in place—a very high-profile win for Texas. The victory provided a key roadmap for other attorneys general in the years that followed.

When President Donald Trump was inaugurated, it was the liberals’ turn at bat. Within days of Trump taking office, the ACLU brought a suit challenging the new Administration’s ban on foreign nationals from seven predominantly Muslim countries from visiting the U.S. Over the course of his tenure, the Trump Administration was sued hundreds of times over immigration policies. Overall, the Trump Administration was sued 110 times by then California Attorney General Xavier Bacerra, a Democrat, according to an analysis by CalMatters, and at least 400 times by the ACLU in lawsuits. The lawsuits contested a range of immigration, environmental, and other types of executive policies.

Another reason for the recent explosion of court challenges was the pace at with the Trump Administration moved on immigration issues. Over the course of his presidency, he enacted 472 immigration policy changes according to the Migration Policy Institute, a bipartisan research institution. That “unprecedented pace” begot an unprecedented wave of new lawsuits. “That really accelerated the legal challenges,” Yale-Loehr says.

After President Biden was inaugurated, conservatives picked up where liberals had left off. “Conservative states are suing every chance they get to challenge everything that the Biden Administration is doing on immigration,” Yale-Loehr says.

An explosion of confusion at U.S. borders

Texas Attorney General Paxton’s most recent lawsuit targets the Biden Administration’s tweak to asylum processing designed to eliminate immigration court backlogs. The idea is that, by allowing asylum officers to decide straightforward asylum cases, rather than always relying on an immigration judge, authorities can drop the wait time for asylum cases from an average few years to a few months. The Department of Homeland Security (DHS) and the Department of Justice (DOJ) first announced the shift on March 24, saying it would go into effect on May 31. Texas filed suit on April 28.

The asylum tweak coincides with the Administration’s attempt to end Title 42, a controversial COVID-19 health measure implemented in March 2020 that the government has used to immediately expel thousands of migrants, including those planning to claim asylum. Title 42 expulsions are slated to end on May 23, and DHS says it expects an uptick in migration flows as a result, including an increase in people seeking asylum. Granting asylum officers the authority to decide some cases, DHS says, will help address growing migration at the U.S.-Mexico border.

But at this point, that entire policy—the Administration’s move to end Title 42, as well as its move to mitigate the effects of ending Title 42—are mired in court. On April 4, Louisiana, Missouri, and Arizona sued to block the Administration from ending Title 42 at all. The states’ challenge came on the heels of another lawsuit, brought by the ACLU and other organizations, demanding that the Biden Administration end Title 42 immediately.

This fog of judicial warfare has resulted in a confusing patchwork of temporary policies. On March 4, the D.C. Circuit Court of Appeals ruled that DHS can expel migrants under Title 42, but could not return families to a country where they faced fear of persecution or torture. That same day, Texas District Court Judge Mark Pittman ruled that the Biden Administration can’t exempt unaccompanied migrant children from Title 42 expulsions.

“That kind of back and forth is just terrible for any sort of consistency or continuity in any policy,” Cardinal Brown says.

Meanwhile, the Supreme Court will weigh in this summer on whether the Biden Administration can end MPP, also known as “Remain in Mexico” policy.

Congress fails to pass any real immigration reform

President Joe Biden sent an immigration reform bill to Congress on his first day in office, but it hasn’t gone anywhere. On Sunday, Democratic Sen. Bob Menendez of New Jersey, the bill’s lead sponsor, told Politico that there is “zero” chance immigration reform will come this year, even though Democrats hold a slim majority in the House and Senate.

The odds of passing Biden’s comprehensive immigration reform bill may worsen after the midterms, when Democrats are widely expected to lose seats.

Last week, a bipartisan group of Senators including Dick Durbin, Ill., Alex Padilla, Calif., Thom Tillis, N.C., and John Cornyn, Texas, resumed discussions of passing immigration measures, according to Roll Call. Even their efforts are unlikely to go anywhere, many Americans may be happy to see that discussions are taking place. According to a 2020 Pew Research Center survey, 75% of Americans say they support Congress creating a legal pathway to citizenship for undocumented people, including 57% of Republicans or those who lean Republican, and 89% of Democrats or those who lean Democratic.

“The American public overwhelmingly supports immigration,” Mukherjee of Columbia says. “The challenge is that our Congress is not functional.”