The Department of Homeland Security considered — but says it rejected — letting governors in 11 states decide whether to deputize their National Guards to enforce immigration law, including helping to detain and deport unauthorized immigrants.

The memo, first reported by the Associated Press Friday, matches the description of a memo leaked to Vox. The memo lays out several possible policies to help implement President Donald Trump’s executive order regarding border enforcement.

The White House strongly denied the report, calling it “100% not true.” A spokesperson for the Department of Homeland Security says the memo was a very early draft, and the idea for National Guard mobilization was “never seriously considered.”

A DHS official says memo was "a very early, pre decisional draft... and was never seriously considered by the Department" — Dorey Scheimer (@DoreyScheimer) February 17, 2017

The memo described by the AP and the memo leaked to Vox were both dated January 25, 2017 — the same day that President Trump signed the executive order in question. That’s consistent with DHS’s statement that it’s an “early draft.”

DHS has not yet formalized its plan to implement the executive order for border enforcement. The memo reported by the AP and posted by Vox appears to still be under consideration in some form, but it’s not clear how substantially it’s been revised.

It’s uncertain whether the National Guard provision has survived in any form — including mobilizing National Guard units for border enforcement, as happened under both George W. Bush and Barack Obama. Nor is it clear whether any of the other policies considered in the draft memo will be implemented.

But the fact that it was floated at all is still significant. President Trump arrived in office on the promise of a sweeping crackdown on immigration enforcement, and proceeded to sign executive orders that made substantial changes — but didn’t always provide details.

The suggestion to deputize the National Guard indicates that the federal government is trying to think big about what implementing Trump’s vision on immigration would look like — even if it ends up rejecting some of its most aggressive ideas.

Using the National Guard to arrest unauthorized immigrants in the US would be unprecedented

The federal government has signed agreements to deputize other government officials to arrest and detain immigrants before. But those agreements, known as “287(g) agreements” under the provision of federal law that authorizes them, have traditionally been signed with local law enforcement agencies: police departments and sheriff’s offices.

Under George W. Bush, 287(g) agreements allowed police officers to engage in immigration arrests and raids as part of “task forces.” Obama curbed the use of those task forces, which had been widely criticized for inspiring fear in immigrant communities and chilling immigrants’ willingness to report crimes to police, as well as raising constitutional concerns about local versus federal authority.

It’s been widely expected that the Trump administration would start deputizing local police to start enforcing immigration law again.

But deputizing National Guard members to do so would have gone much farther — and could raise questions about posse comitatus, which is intended to draw a sharp line between the military and domestic law enforcement.

According to the draft memo, the National Guard option would be given to governors in “states adjacent to the land border with Mexico and […] those states adjoining such border States,” per the draft memo. As the AP has pointed out, this covers 11 states — from Oregon in the Northwest to Louisiana in the Southeast.

Here’s the relevant passage from the memo:

I am directing the Commissioner of CBP and the Director of ICE to immediately engage with the Governors of the States adjacent to the land border with Mexico and to those states adjoining such border States for the purpose of entering into agreements of section 287(g) of the INA to authorize qualified members of the state National Guard, while such members are not in federal service, or qualified members of a state militia or state defense force under the command of the Governor, to perform the functions of an immigration officer in relation to the apprehension, investigation and detention of aliens in the United States.

You can read the full memo, as leaked to Vox, here.