A federal judge in Texas struck down the state's attempt to let local police arrest and deport illegal immigrants, ruling that the law trampled federal authority and comparing the effort to pre-Civil War nullification doctrine.
U.S. District Judge David Ezra issued a preliminary injunction blocking Texas Senate Bill 4 before its scheduled March 5 effective date, as Courthouse News reported. The ruling handed a win to the Biden administration, which challenged the law as unconstitutional, and set the stage for what has become one of the most consequential federal-state legal battles over border security in a generation.
SB 4, championed by Governor Greg Abbott, would have allowed Texas state and local law enforcement to arrest migrants suspected of crossing illegally from Mexico between ports of entry. State judges could then order those individuals returned to Mexico. Texas Attorney General Ken Paxton immediately appealed the ruling.
The legislation represented Texas's most aggressive effort yet to claim a direct role in immigration enforcement, a domain the federal government has long treated as exclusively its own. Under SB 4, any migrant suspected of entering the country illegally through the Texas-Mexico border could face arrest by a state trooper or local officer, not just a federal agent.
State judges would then have had the power to order those individuals removed to Mexico. That provision drew fierce opposition from the Biden administration, civil rights groups, and the Mexican government, which stated it would not accept migrants returned to its territory by Texas under the measure.
The law reflected a broader strategy by Abbott, who has spent years escalating state-level border enforcement through razor wire barriers, National Guard deployments, and busing migrants to Democratic-led cities. SB 4 went further than any of those steps by inserting state courts directly into the deportation process.
Judge Ezra ruled the law likely violated the Constitution and Supreme Court precedent holding that immigration enforcement authority belongs to the federal government. His opinion rejected Texas's core legal argument: that the volume of illegal border crossings constituted an "invasion" that triggered the state's sovereign right to defend itself.
National Review reported that the judge framed his ruling in stark historical terms. Ezra wrote:
"To allow Texas to permanently supersede federal directives on the basis of an invasion would amount to nullification of federal law and authority, a notion that is antithetical to the Constitution and has been unequivocally rejected by federal courts since the Civil War."
That language carries real weight. Nullification, the idea that a state can void federal law within its borders, is a legal concept most associated with the antebellum South. By invoking it, Ezra placed Texas's argument outside the boundaries of accepted constitutional debate.
For conservative legal observers, the ruling raises a familiar tension. The federal government claims exclusive power over immigration enforcement but, under the Biden administration, has drawn sharp criticism for failing to exercise that power at the southern border. Texas officials have argued the state has no choice but to act in the absence of adequate federal action. The pattern of federal judges blocking state and executive policy efforts has become a recurring flashpoint in American governance.
The legal fight did not end with Judge Ezra's injunction. The case rapidly escalated through the federal courts, producing a whiplash sequence of orders that underscored how unsettled the legal ground remains.
The Supreme Court briefly allowed SB 4 to take effect, lifting the lower court's block. But within hours, the 5th U.S. Circuit Court of Appeals barred Texas from enforcing the law again, as the New York Post reported. The rapid reversal left the law in legal limbo and the state's enforcement apparatus frozen.
Justice Sonia Sotomayor dissented from the Supreme Court's initial decision to let SB 4 proceed, warning of the consequences:
"The Court gives a green light to a law that will upend the longstanding federal-state balance of power and sow chaos."
Sotomayor's dissent reflected the position of the Biden administration and immigration advocates who argued that allowing 50 states to craft their own immigration arrest and removal schemes would create an unworkable patchwork of enforcement regimes. Supporters of SB 4 countered that the federal government's failure to secure the border left Texas with no viable alternative.
Ken Paxton's immediate appeal signaled that Texas had no intention of accepting the district court's ruling as the final word. The case moved to the 5th Circuit, widely considered the most conservative federal appeals court in the country, giving Texas supporters reason to believe the law could eventually survive judicial review.
The legal question at the heart of the dispute is whether the federal government's exclusive authority over immigration can be challenged when that authority is, in the eyes of border states, exercised inadequately or not at all. Texas has framed SB 4 not as a replacement for federal enforcement but as a necessary supplement to it. A separate ruling later in the litigation would clear the way for parts of the Texas enforcement framework, though the legal landscape has continued to shift.
The Biden administration's position, backed by Judge Ezra's ruling, holds that the Supremacy Clause of the Constitution and decades of precedent leave no room for states to conduct their own immigration arrests and removals, regardless of how overwhelmed the border may be.
The international dimension of SB 4 added another layer of complexity. Mexico stated flatly that it would not accept migrants returned to its territory by Texas under the law. That position created a practical problem for enforcement even if the legal challenges failed: without Mexico's cooperation, state judges ordering removal to Mexico would be issuing orders with no mechanism for compliance.
Federal immigration enforcement operates through diplomatic agreements and bilateral processes that individual states cannot replicate. The Mexican government's refusal to participate in a Texas-run removal process highlighted the gap between the law's ambitions and the realities of cross-border enforcement. Questions about the proper scope of judicial and governmental authority have drawn increasing public scrutiny in recent years.
SB 4 sits at the intersection of two powerful forces in conservative legal thought. On one side stands the principle of state sovereignty, the idea that states retain broad authority to protect their citizens when the federal government will not. On the other stands the constitutional structure that assigns immigration power to Congress and the executive branch.
Judge Ezra's nullification framing stung Texas officials precisely because it cast their argument as constitutionally illegitimate rather than merely incorrect on the merits. The ruling did not simply say Texas got the law wrong. It said Texas was attempting something the constitutional order forbids.
Whether the 5th Circuit or the Supreme Court ultimately agrees with that characterization will shape the boundaries of state power on immigration for years. The case has drawn comparisons to other high-profile clashes where judges have intervened aggressively in politically charged disputes, raising questions about the judiciary's role as a check on elected officials.
For now, SB 4 remains blocked. Texas police cannot arrest migrants under state authority, and state judges cannot order anyone deported. The border remains a federal responsibility, enforced, or not, at the federal government's discretion.
When the people tasked with enforcing the law refuse to do so, and the people willing to step in are told they cannot, someone ought to ask who exactly is supposed to secure the border.
