We all need to fight the temptation to abandon constitutional principles when they conflict with our policy preferences.

I recently appeared on a radio show to talk about the Tenth Amendment and nullification. The conversation moved along marvelously as I explained Madison’s blueprint, and how state and local governments can thwart unwarrantable federal actions (and even warrantable actions that happen to be unpopular) by simply refusing to cooperate with officers of the union. The host loved the application of Madison’s advice to federal gun control, asset forfeiture and even the “war on drugs.”  But he said there was one current nullification movement he absolutely opposed.

Sanctuary cities.

Then he asked me about my position on the issue.

Talking about sanctuary cities and immigration on a conservative radio show feels a lot like walking through a minefield.

Many conservatives who generally love efforts to confront federal authority suddenly become ardent federal supremacists when it comes to immigration. They want the feds to come down hard on sanctuary cities. They support “defunding” them to the fullest extent possible. Some even want the feds to arrest city officials in sanctuary cities.

So, how do you explain the constitutional justification of sanctuary cities and their strategic importance in the broader context of American constitutionalism without alienating the entire audience?

Here’s how I explained it on the show.

The key is in separating the constitutional and policy issues.

So, the first question to ask is whether a local jurisdiction can operate as a sanctuary city (or state) within the American constitutional system.

The answer is yes.

In fact, sanctuary city supporters follow Madison’s blueprint for limiting federal power – a refusal to cooperate with officers of the union. Even the Supreme Court has upheld this principle through the well-established 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. In the foundational case, the Court held that the federal government could not force states to assist in fugitive slave rendition.

“The fundamental principle applicable to all cases of this sort, would seem to be, that where the end is required, the means are given; and where the duty is enjoined, the ability to perform it is contemplated to exist on the part of the functionaries to whom it is entrusted. The clause is found in the national Constitution, and not in that of any state. It does not point out any state functionaries, or any state action to carry its provisions into effect. The states cannot, therefore, be compelled to enforce them; and it might well be deemed an unconstitutional exercise of the power of interpretation, to insist that the states are bound to provide means to carry into effect the duties of the national government, nowhere delegated or instrusted to them by the Constitution.”

Joseph Story’s opinion in Prigg affirmed a basic pillar of American constitutionalism – separation of powers. The federal government has its sphere of authority, and the states have their sphere of authority. The federal government can’t force state to act within the federal sphere.

This includes mandating local jurisdictions must enforce federal immigration.

Affirming the legitimacy of sanctuary cities doesn’t mean you have to support the policy. But you shouldn’t call on the federal government to stop it. When you insist the feds should use their power to shut down sanctuary cities, you obliterate separation of powers. Ultimately, you risk destroying the most powerful tool states have to confront federal authority. When you break down the wall between the federal and state spheres, you can’t put it back up when you need it later. Once you’ve admitted federal power into the realm of state and local authority, it will never go away.

So, if you oppose sanctuary cities, what do you do?

Stop them at the state level.

While the federal government cannot legitimately prohibit sanctuary cities, states have full control over their political subdivisions. For instance, Texas passed a bill that effectively bans sanctuary cities. Tenth Amendment Center executive director Michael Boldin summed it up perfectly.

“Whether that’s good policy or bad policy for Texas is up to Texas. But it’s a decision for Texas, not Washington D.C.”

Instead of begging the federal government to intervene and put the kibosh on sanctuary cities, those who support the constitution and limited federal authority would be better served to take a page from the sanctuary city playbook. Use the same formula to create sanctuary cities and states for guns. In the same way opponents of tough immigration laws have hindered enforcement through local policies of noncooperation, you could hinder federal gun control using the same strategy.

If we truly care about the Constitution, we must avoid doing anything that will further empower the federal government above all else. If that means sacrificing some of our policy preferences, we should always chose that course. We should place constitutional principle over our desired policy outcomes every single time.

James Madison did this.

His last act as president was to veto an internal improvements bill that would have funded the construction of roads and canals. He approved of the policy. But he refused to sign it into law because, “The legislative powers vested in Congress are specified and enumerated in the eighth section of the first article of the Constitution, and it does not appear that the power proposed to be exercised by the bill is among the enumerated powers, or that it falls by any just interpretation with the power to make laws necessary and proper for carrying into execution those or other powers vested by the Constitution in the Government of the United States.”

Madison put constitutional fidelity over his policy preference.

We should do the same.

Every issue.

Every time.

No exceptions.

No excuses.