Moina Shaiq holds a sign at a rally in San Francisco on Jan. 25. On April 25, a federal judge blocked a Trump administration order to withhold funding from communities that limit cooperation with U.S. immigration authorities, saying the president has no authority to attach new conditions to federal spending. (Jeff Chiu/AP)

Last Tuesday, a federal judge in San Francisco temporarily blocked President Trump’s executive order on “enhancing public safety.” This order threatened to withhold federal funding from any jurisdiction that did not fully comply with federal immigration laws and with any additional requests made by federal immigration authorities. The judge, William H. Orrick, found that Trump’s executive order likely violated the Constitution because it overextended the federal government’s power to enforce immigration laws.

The White House described this angrily as an “unelected judge unilaterally [rewriting] immigration policy for our Nation,” claiming that the ruling was a “gift to the criminal gang and cartel element in our country, empowering the worst kind of human trafficking and sex trafficking,” and depicting the ruling as a blow in a fight between “rule of law” and “lawlessness.” In fact, however, Orrick was relying on a set of constitutional arguments that have been promoted by conservative legal groups, most prominently the Federalist Society for Law and Public Policy Studies.

Conservative legal activism pushed arguments for state sovereignty into the mainstream

In his decision, Orrick relied primarily on the constitutional doctrine of state sovereignty. This doctrine argues that the Constitution limits the power of the federal government and protects state and local governments from being unduly coerced by or co-opted into federal programs. These principles and doctrines, contrary to what  Trump and his staff have asserted on social media and otherwise, are not novelties created by liberal activist judges. Instead, these principles emerged in conservative legal challenges to sweeping federal laws that began in the mid-1990s and culminated in the successful 2012 legal challenge to the Affordable Care Act, or Obamacare.

Until the late 1970s, there was a widely shared sentiment within the legal profession and the academy that the 10th Amendment to the U.S. Constitution (which states, “The powers not delegated to the United States by the Constitution, nor prohibited by it to the states, are reserved to the states respectively, or to the people”) was a relic of history that had become constitutionally irrelevant. Some even pronounced the 10th Amendment dead in light of the dawn of an era of cooperative federalism — a system where federal, state and local governments share responsibility for governance and interact cooperatively.

But one group dissented from the prevailing view of federal-state relations. In the early 1980s, the Federalist Society for Law and Public Policy Studies — at that time a ragtag collection of conservative and libertarian law students, professors, litigators and judges — began to push for a revival of the 10th Amendment and the attendant doctrine of state sovereignty. In 1982, the Federalist Society’s first national conference featured several speeches arguing that power should be taken away from an overreaching federal government and given back to the states and local governments through the 10th Amendment. Speeches such as “The Revival of States’ Rights” and “In the Beginning Are the States” decried the “suffocating” and destructive consequences of federal programs that put “coercive” conditions on the states. These speakers didn’t see the relationship between federal government and the state as being “cooperative” relationships. Instead, they harped on the coercive elements of federal programs, arguing that they deprived states and local governments of autonomy and self-rule.

This changed minds on the Supreme Court

By the early-1990s, the Supreme Court — with three Reagan and two George H.W. Bush appointees —  had become more receptive to Federalist Society arguments about federalism and state sovereignty. As Hollis-Brusky writes in “Ideas with Consequences,” a 1992 case led the Supreme Court to strike down a federal law that required states to either comply with federal radioactive waste regulations or assume ownership of the waste. Writing for the majority in that case (and citing Federalist Society member Michael W. McConnell’s scholarship), Justice Sandra Day O’Connor wrote that the federal government cannot coerce state and local governments to participate in programs.

In 1997, a conservative majority of the Supreme Court struck down the Brady Act’s requirement for state law enforcement officials to conduct background checks on anyone seeking to buy a handgun. In his majority opinion, Justice Antonin Scalia — explicitly relying on four different articles written by prominent Federalist Society scholars — wrote that the Constitution prohibited the federal government from “commandeering” state resources and “conscripting” state law enforcement officials into carrying out federal programs. This doctrine became known as the Anti-Commandeering Doctrine and was widely praised and celebrated by conservatives as a victory for the 10th Amendment and state sovereignty.

This robust conception of state sovereignty as a shield against federal overreach won an even bigger victory in the 2012 Obamacare case, NFIB v. Sebelius. While Chief Justice John G. Roberts Jr. drew highly publicized ire from Federalist Society circles for his alleged flip-flop on the individual mandate provision of the Affordable Care Act (upholding it under the federal government’s taxing power), the case was actually a blockbuster win for 10th Amendment enthusiasts. In Sebelius, seven of the justices agreed that requiring states to expand Medicaid was coercive. In its opinion, the Supreme Court reiterated that the federal government cannot require state governments to participate in a federal program or force states to comply by threatening large portions of federal funding.

Sanctuary cities are flipping these arguments against the Trump administration

Today, nearly five years since the Supreme Court’s decision in NFIB and more than 20 years since the introduction of the Anti-Commandeering Doctrine, the Federalist Society’s robust conception of state sovereignty is well-established constitutional doctrine. Faced with the immigrant-hostile Trump administration, many sanctuary cities are flipping the script. If the federal government cannot force conservative states to participate in waste disposal programs, or conduct background checks for firearms, or expand Medicaid, then surely it cannot force or “coerce” state and local governments to carry out immigration orders.

San Francisco County and Santa Clara County decided to test their theories in court by suing the federal government. Judge Orrick agreed with their arguments. Taking a page out of the Federalist Society’s playbook, Orrick found that the executive order was likely unconstitutional because it was coercive and because it commandeered state resources.

Orrick also leveraged some of the Federalist Society’s hard-won cases in his ruling against the Trump administration. Quoting the 1992, 1997 and 2012 cases, he wrote that the executive order was essentially a “gun to the head” and that the Supreme Court has repeatedly held that the federal government “cannot compel the States to enact or administer a federal regulatory program.”

The principles that Orrick relied on, as mentioned earlier, are not new. Nor are they the product of activist liberals scheming to undermine the Trump administration. Rather, they are the product of the ideological vision of the conservative Federalist Society.

As Trump seeks to realize his vision for the nation, he will need the cooperation of state and local governments. This might have been easier under the pre-1970s understanding of federalism. If instead of help he gets lawsuits blaming him for “commandeering” states, he should not attack liberal judges, and should instead be blaming conservative legal activists.

Amanda Hollis-Brusky is associate professor of politics at Pomona College in Claremont, Calif. She is the author of “Ideas with Consequences: The Federalist Society and the Conservative Counterrevolution.”

Jerry Yan is a rising senior studying politics at Pomona College.