SPRINGFIELD, Ill. (Aug. 10, 2021) – Earlier this month Illinois Gov. J.B. Pritzker signed a bill into law limiting state cooperation with federal immigration enforcement.
Sen. Omar Aquino (D-Chicago) sponsored Senate Bill 667 (SB667). The new law expands the Illinois Trust Act passed in 2017 prohibiting state and local police from holding a person solely on the basis of a federal immigration detainer. SB667 expands the law to prohibit law enforcement officers from inquiring about or investigating the citizenship, immigration status, or place of birth of any individual in custody, or who has otherwise been stopped or detained.

This provision will effectively do an end-run around  8 USC 1373. Under this law, states and localities cannot ban information sharing with the feds related to a person’s immigration status. But if state and local law enforcement officers are prohibited from asking about immigration of citizenship status, they can’t violate the federal law in question. They can’t share information they don’t have.

Some prominent constitutional scholars, including Ilya Somin, argue that this federal act is also unconstitutional and represents an illegal commandeering of state resources.

SB667 also more broadly bars state and local cooperation with federal immigration enforcement. A law enforcement agency or official cannot participate, support, or assist in any capacity with an immigration agent’s enforcement operations unless presented with a  federal warrant or as otherwise required by federal law. This includes any collateral assistance such as coordinating an arrest in a courthouse or other public facility, providing use of any equipment, transporting any individuals, or establishing a security or traffic perimeter surrounding such operations. This provision prohibits several specific actions, including allowing direct access to state and local law enforcement databases to federal immigration enforcement, granting federal immigration officers access to an individual in state or local custody, and transferring any individual into a federal immigration agent’s custody.

On May 28, the Senate passed SB667 36-19. On May 31, the House approved the measure 68-47. With Gov. Pritzker’s signature on Aug 2, the law went into immediate effect.


While the law does not allow state agencies to directly interfere with federal immigration enforcement, it will leave the ICE to enforce immigration law by itself in many situations. This will likely make it much more difficult for the federal government to enforce federal immigration law in Illinois.

Based on James Madison’s advice for states and individuals in Federalist #46, a “refusal to cooperate with officers of the Union” represents an extremely effective method to bring down federal gun control measures because most enforcement actions rely on help, support and leadership from the states.

Fox News senior judicial analyst Judge Andrew Napolitano agreed. In a televised discussion on gun control, he noted that a single state taking this step would make federal gun laws “nearly impossible” to enforce.

With immigration, federal resources are even more stretched, as noted in a column published by The Hill.

As the U.S. Immigration and Customs Enforcement (ICE) Enforcement and Removal Operations (ERO) notes on its website, the first and foremost factor impacting its enforcement capability is “the level of cooperation from state and local law enforcement partners.”

With just over 5,700 agents nationwide, ERO reported removal of “240,255 aliens in FY 2016.” In spite of the supposedly high number of sanctuary cities nationwide, this number actually represented an uptick from 2015 due partly to what ERO called “increased state and local cooperation.”

At this rate, removing anywhere close to the at least 11 million unauthorized immigrants in the country right now seems impossible.

Simply put, partnerships don’t work too well when half the team quits. And in this case, when most of the team stops participating.


Provisions withdrawing state and local enforcement of federal law in SB667 rest on a well-established legal principle known as the anti-commandeering doctrine. Simply put, the federal government cannot force states to help implement or enforce any federal act or program.

The anti-commandeering doctrine is based primarily on four Supreme Court cases dating back to 1842. Printz v. US (1997) serves as the cornerstone. In it, Justice Scalia wrote for the majority:

“We held in New York that Congress cannot compel the States to enact or enforce a federal regulatory program. Today we hold that Congress cannot circumvent that prohibition by conscripting the States’ officers directly. The Federal Government may neither issue directives requiring the States to address particular problems, nor command the States’ officers, or those of their political subdivisions, to administer or enforce a federal regulatory program. It matters not whether policy making is involved, and no case by case weighing of the burdens or benefits is necessary; such commands are fundamentally incompatible with our constitutional system of dual sovereignty.”

Additionally, in the 1842 Prigg v. Pennsylvania case, the Court held that while the federal Fugitive Slave Act could not be physically impeded by states, they simply weren’t required to help the federal government capture runaway slaves and return them to bondage in the South.

No determination of constitutionality is necessary to invoke the anti-commandeering doctrine. State and local governments can refuse to enforce federal laws or implement federal programs whether they are constitutional or not.

Mike Maharrey

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