Since President Donald Trump assumed office in January, one of his top priorities has been the strict enforcement of immigration laws, including the zealous deportation of undocumented immigrants. His main action to this point has been to issue several flawed executive orders, including one that bars federal funds from sanctuary cities except when mandated by law. This order, signed on Jan. 25, gave rise to many questions. Is the order constitutional? What qualifies as a sanctuary city or university? Can locations avoid the official label of “sanctuary” while still working to protect their undocumented community members? While revisions to the order continue to roll in almost weekly, its unconstitutionality has already become glaringly obvious. It has been defeated in court three times so far, but its ultimate fate is still unclear.

The executive order defines sanctuary cities and universities as “jurisdictions across the country [that] willfully violate federal law in an attempt to shield aliens from removal from the United States.” Under the terms of the executive order, federal authorities would legally have the right to detain or deport any undocumented immigrants, even those who have just overstayed their green cards. Recently, Trump announced revisions to the executive order that essentially enlist local police officers as immigration officers. Both of these elements of the order violate the U.S. Constitution as interpreted by the Supreme Court.

The Supreme Court’s 1987 decision in South Dakota v. Dole established that federal funding cuts that are implemented for unduly coercive reasons are unconstitutional. However, Trump is threatening cities and universities that fail to comply with his executive order with cuts in federal funding, thus likely violating the standard established by Dole.

The 10th Amendment states that powers not specifically delegated to the federal government by the Constitution will be left to the states. According to the Supreme Court’s 1992 decision in New York v. United States, this means that states cannot be compelled to enforce federal regulations. Initially, Trump’s executive order only asserted that jurisdictions could not withhold any information regarding an individual’s immigration status from federal authorities. As of Feb. 21, however, the executive order was revised to include a clause that would compel local police officers to enforce federal immigration law. Commandeering local police officers to enforce federal law is the blatant violation of states’ and cities’ 10th Amendment rights.

Whether a city or university is considered a sanctuary location largely depends on that location’s willingness to officially declare itself a sanctuary. The threat of Trump’s executive order may have deterred locations that otherwise might have declared themselves as sanctuary locations from doing so for fear of losing needed federal funding. However, a location can still unofficially carry out many of the functions of a sanctuary location, even if it doesn’t embrace the official designation.

Stanford University is one example of a place that rejects the sanctuary label yet implements many sanctuary-like policies. Stanford president Marc Tessier-Lavigne officially rejected students’ efforts to make Stanford University a sanctuary campus, mostly for fear of federal sanction.

However, Tessier-Lavigne reaffirmed the values of many of Stanford’s students who are actively advocating for sanctuary campus status, according to CBS San Francisco Bay Area. Stanford’s website indicates that the university is taking measures such as keeping student records completely private, having their law school help pro-bono with legal cases involving undocumented individuals and their immigration status, keeping local law enforcement from inquiring about immigration status and showing strong support for the BRIDGE Act, a new piece of legislation that would preserve the rights of those who are in the United States under DACA.

Is the refusal of a city to enforce federal law enough to qualify that location as a sanctuary? While a formal declaration shows deliberate intent to protect undocumented people, I would argue that the refusal to act based on the sheer unconstitutionality of Trump’s executive order is, in a way, a quiet and legal protest against the moral consequences of the executive order.

Many locations that decline to officially declare themselves as sanctuaries do so out of fear of losing federal funding. The best course of action for these places is to refuse to assign local police officers to immigration investigations and refuse to actively investigate and detain suspected undocumented immigrants through local police forces. These actions are legal and protected by the 10th Amendment; the burden of enforcing federal law falls on the federal government, not on states and cities.

Not all cities or universities can or should officially declare sanctuary status, depending on their financial situations or the makeup of the constituents who reside there. However, Trump’s executive order is a federal infringement upon the rights of the all states and cities; irrespective of their views on immigration this is not an issue that should be taken lightly. Cities should fight back on this executive order — it has the potential to significantly impact not only the lives of undocumented individuals in the United States but also states’ rights as we know them.