On January 25, 2017, days after stepping into office, President Trump issued an executive order entitled “Enhancing Public Safety in the Interior of the United States,” which threatened to withhold federal grants from any “sanctuary jurisdictions” in the U.S. The pronouncement, which potentially could affect some 150-300 cities and communities that might be construed as “sanctuary” entities, rested its authority on section 1373 of the U.S. code, which requires local governments to permit local officials to send information regarding the citizenship or immigration status of individuals to federal officials, in this case Immigration and Customs Enforcement (ICE).

The order, it should be emphasized, did not simply order sanctuary jurisdictions to cooperate with federal immigration officials. It threatened them with economic punishment if they did not do so. The aggressive stance, apparently pushed hard and articulated by Bannonists in the White House, was followed by misleading and false statements by administration officials aimed at sanctuary proponents, accusing them of encouraging crime and endangering American lives.

The recent passing of pro-sanctuary legislation, including California’s Sanctuary Law, effective on January 1, 2018, have brought the administration’s threats to a new level. Acting head of ICE, Thomas Homan, suggested in one interview that politicians instituting sanctuary policies should be charged with criminal offenses. Anti-immigration voices on social media and sundry news outlets have chimed in with a drumbeat of outrage. In its recent coverage, for example, Fox News featured misleading comments by sanctuary opponents and a photograph of a highway sign in California erected by unidentified individuals stating “Official Sanctuary State: Felons, Illegals and MS13 Welcome! Democrats Need the Votes.”

For their part, sanctuary supporters have launched law suits questioning the constitutionality of Trump’s executive order. Progressive writers like Ian Reifowitz on Daily Kos and sites like Lawfare have tried to clarify the issues and make the progressive argument for sanctuary. States like California have publicly debated the issue. But the mainstream media has been largely AWOL on sanctuary, and the challenges of overcoming the Trumpian law-and-order fog is considerable. Amongst the general public there is general confusion about most aspects of sanctuary, and polls reflect it.

To help dispel some of the confusion, we offer answers to a few common questions that often arise about the sanctuary issue:

Q: What is a sanctuary jurisdiction?

A: There is no agreed upon definition. Advocates like Mayor Eric Garrett of Los Angeles as well as opponents like John Kelley, former head of the Department of Homeland Security, have shied away from the question. But here is a stab at it: A sanctuary jurisdiction is a state or locality that adopts policies that minimize, consistent with the U.S. Constitution, its cooperation with federal immigration authorities seeking to find and remove illegal immigrants with no criminal record.

Q: What is the rationale for instituting sanctuary policies in the first place?

A: The purpose of sanctuary policies is to safeguard communities from federal intervention that has the potential to disrupt, divide, and instill fear among their residents. By insulating local law enforcement from involvement in federal round-ups, such policies enhance the sort of trust between local police and residents that enables individuals to report crimes and problems without fear of being deported for immigration violations. Far from protecting criminal gangs and drug cartels, as opponents claim, sanctuary policies help to isolate such elements and make them less able to find refuge in the surrounding population.

Q: Is there a historical precedent for sanctuary policies?

A: Yes, many cities have been relying on sanctuary policies since the 1980s and 90s, although the policies were once not called by that name. Police departments have mostly been strongly in favor of them because they promoted good relations between law enforcement and residents. Trump-supporter Rudy Giuliani governed New York City for years, for example, with policies that prevented heavy-handed federal intervention and maintained good relations with immigrant communities.

Q: Don’t federal authorities have the right to  demand that local and state authorities cooperate in enforcing federal law?

A: It depends a lot on what degree of cooperation is meant. In general, states and local authorities have wide autonomy in choosing whether to deploy their resources, already stretched in most cases, for the purpose of enforcing federal laws. Nowhere does the Constitution expressly empower the federal government to force states to do so. Moreover, the 10th Amendment to the Constitution asserts that “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.”

Thus efforts by the federal government to force states and localities to use their resources to enforce federal laws, often described as “commandeering,” are generally viewed by courts as coercive and unacceptable. Among other things, they conflict with the notion of federalism and the division of power. According to Jane Chong, a scholar writing for lawfareblog.com, “commandeering infringes on state sovereignty by allowing the federal government to shift the financial burden of its policies to the states and also to escape political accountability by confusing voters about where to lay the blame or credit for those policies.”

Q: Short of commandeering, do federal authorities have the right to require lesser kinds of cooperation from the states, such as providing information to assist in enforcing federal laws?

A: This is a cloudier area than outright “commandeering,” since such a requirement is less burdensome to the state or community. Section 1373 itself, the ordinance referred to in Trump’s January 25 executive order, is an information-related directive couched in careful language to make it appear not too coercive. It requires local governments to permit their officials to send information regarding the citizenship or immigration status of any individual to federal authorities like ICE. The courts will eventually have a chance to decide whether this is constitutional. Even if it is so considered, many sanctuary jurisdictions render the issue moot by already agreeing to supply information on the citizenship or immigration status of individuals. San Francisco argues, for example, that it is actually in compliance with 1373.

Q: Are there any recent court precedents that limit the ability of federal authorities to require cooperation from states in enforcing federal law?

A: Yes. In Printz v. United States, decided in 1997 by the Supreme Court, the majority ruled that the Brady Bill threatened the “residual and inviolable sovereignty” of the states by “commandeering” sheriffs to perform background checks on gun buyers, in violation of the 10th Amendment. Right-leaning Justice Antonin Scalia was the author of the opinion, an ironic twist given that people on the right are now demanding states and localities comply with federal enforcement demands.

Q: Opponents of sanctuary policies assert that such policies protect criminals. Is this true?

A: This is a common misperception. Although they try to shield law-abiding immigrants from federal round-ups, sanctuary jurisdictions are just as interested in stopping criminals as anybody else. Indeed, they “routinely” cooperate with ICE in deporting actual criminals. Sanctuary legislation makes this possible. For example, California’s new sanctuary law, in effect since January 1, enables police and sheriffs to transfer people to immigration authorities if they have been convicted within the last 15 years of any one of some 800 felonies and misdemeanors.

Q: Can federal authorities actually withhold funds from so-called sanctuary entities as a means of punishing them?

A: This is mostly a bogus threat with little constitutional basis. Congress does have some power to punish states for non-compliance by inserting penalties in the relevant legislation, and even then, only under certain conditions. The precedent for this is Dakota v. Dole (1987), a case in which the Supreme Court upheld Congress’ requirement that states be penalized a certain percent of highway funds if they failed to establish a drinking age of 21. But the penalty had to be related to the purpose of the legislation, in this case highway safety, and be unambiguous.

The executive branch is much more limited than Congress in establishing penalties, and would need a clear rationale and congressional authority to go ahead with them, probably unrealistic hurdles for the Trump administration. Moreover, most federal grants to states are untouchable since some 65% of them come in the form of mandated funding like Medicaid.  Although there is some executive room for partiality built into the federal government’s discretionary budget, it would probably not be enough to seriously affect state and local recipients.