If I hear one more person say something like “Posse Comitatus is what makes us a democracy” I’m going to start throwing things. That is so wrong it’s backward. That law was - and was meant to be - the main facilitator of Jim Crow. Thread.
1/

First: “posse comitatus” refers to the common law doctrine that this 1878 Act was going to ban, i.e. the ability of local law enforcement officials to call for the help of local able men to enforce the law. Britain did/still does allow this, and it was normal to the Founders.
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It was so normal to everyone to use the military for law enforcement that for the first ca. 100 yrs of existence, that’s almost all the Army did. W/ the exception of a couple of wars, the Army did nothing but try to enforce federal law on unruly frontiersmen and grumpy states.
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This mainly consisted of trying to stop frontiersmen from encroaching on Indian land or federal land, as well as resolving local disputes. The Army was in fact in charge of all Indian Affairs, which could include supervising trade and trying to stop the spread of disease.
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After the Civil War, there were two periods of Reconstruction: Johnson’s initial conciliation approach, which so enraged Northern Republicans (w its discrimination and leniency) that the radicals in Congress asserted their power and began a new phase of Reconstruction ...
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In which US forces - often incl black soldiers - were used to enforce black enfranchisement and land rights (against violent suppression by state militias/the KKK). Several Southern states either elected or had Republican govts installed by the feds. This didn’t go over well.
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Around rolls the election of 1876. TLDR: vote was v close and disputed, leading to the Compromise of 1877: Dems in the House would accept the electoral commission’s rec of awarding the win to Hayes IF he pulled all fed troops out of their role protecting R govts in the South
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... and ended the aggressive phase of Reconstruction. He and the Rs in Congress agreed, Grant/Hayes pulled all Fed troops out of Confederate states, restoring “home rule” (which meant “white people rule”). The Dems introduced the Posse Comitatus Act to prevent relapse.
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The bill was designed to prevent the use of federal troops to enforce civil rights, basically, and to privilege the state militias (later the Natl Guard) b/c the latter were usually more aligned w/, ahem, Local Politics.
It passed, but divided govt does funny things, so ...
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(I should note that it passed w some Republican support, as some felt the use of the military was too heavy-handed and others objected to the frequent use of troops against labor unrest/strikes; this latter issue played a part in Hayes’s decision)
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Ok, so the law does NOT forbid the military from participating in law enforcement. I’ll wait while you read that again and internalize it.
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It forbids any person from USING the military to enforce laws, UNLESS OTHERWISE AUTHORIZED BY CONGRESS OR THE CONSTITUTION.
So the law is aimed at civilian officials who might want to use troops to help locally, such as mayors, governors, sherriffs, marshalls etc.
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It means these peeps can’t just call up the local CO and say “I need you to send me a PLT to help chase down a fugitive”. They CAN request help from the proper authorities, though, which is how you get the USA/USMC showing up to help with riot control and border security.
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Congress has passed further laws clarifying and delineating how the federal troops can be used in aid to civil authorities, and they have included some specific restrictions, which get a lot of air time. What doesn’t get a lot of air time are three important points:
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1) these are just statutes and Congress could change them any time they wanted. They’re not Ur-Principles of American Democracy
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2) the things the statutes ALLOW the president to do are so broadly construable that the constraints are, for practical purposes, very weak and limited;
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3) most presidents have argued that they have the *Constitutional* authority as the chief executive OF THE LAW to use federal troops (or to federalize the NG) to execute federal law when they see fit ... and the fun part is that SCOTUS has chosen not to interfere w that.
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Part of why there is so much misunderstanding of this law is that the DOD *really* does not like doing these things, and has promulgated a narrative that they’re not allowed to. But just do a fun google search of, e.g., the Pullman strikes or the Battle of Blair Mountain.
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SOOOO please stop with both the “it’s totally illegal to use the military on domestic soil!” And the “Posse Comitatus is central to our identity as a democracy!” stuff ... bc it’s not, and it’s not.
END RANT BUT I MAY START AGAIN IF THIS DOESN’T GO AWAY BC AAAARRRGGGHHH

A couple of ppl have asked, so here is some further clarification.
Statutory restrictions are that military can’t engage in arrests, investigations, or seizures *unless otherwise authorized*
NG troops can do these things so long as they’re still under the command of the Gov
PS1/

Stat. authority for Prez to do pretty much whatevs: 10 USC 251-255 (Insurrection Act)
“Whenever the P considers that unlawful obstructions...assemblages, or rebellion...make it impracticable to enforce the laws of the US...by the ordinary course of judicial proceedings...
PS2/

...[prez] may...use such of the armed forces as he considers necessary to enforce those laws or to suppress the rebellion”.
In Martin v Mott (1812) SCOTUS held that authority to determine whether such an exigency had arisen belonged exclusively to the prez (not Cong)
PS3/

An astute reader pointed out that at least one US state still has a law on the books that the local sheriff can call on the local federal troops as a posse, but federal law trumps state on this, and if a CO is asked for such help, CO should politely refuse.
PS4/

Fun story: this actually happened in AL in 2009, when Michael McClendon killed ten people over two counties. Local sheriff called Ft Rucker and asked for back-up. Though the US troops just helped direct traffic etc., an investigation found this to violate Posse Comitatus.
ENDISH

https://twitter.com/carter_pe/status/1240428694109331460?s=21

Since this is getting some more attention, I have an update: I may have discovered the origins of the myth that it’s a fundamental principle of American democracy that militaries aren’t involved in policing.

It has to do w 1) the conflation of “military” w “federal” and 2) the British hatred of all things French.

Research on the origins of professional policing makes clear that a main reason the UK avoided the centralized police model was bc it was French. The UK did introduce professional metropolitan police, but left all other policing to the old local sheriff/neighborhood watch model.

The US copied the UK model in the mid-19th c: only cities had professional police; rural areas remained on the sheriff/posse model. This differed from the French model, in that all French police were professional, the rural ones under central state rather than local authority.

Several British and American commentators claimed that, to be democratic, law enforcement had to be under local, rather than central control. By transitive logic, as the military was under federal control, its use in law enforcement could not be democratic.

In short, this attitude had nothing to do w the idea that militaries should be directed externally or whatnot. It had to do w the fact that many (shockingly, mostly the same ppl who thought secession was cool) thought the federal govt shouldn’t have any hand in law enforcement

This is a big thing in comparative civ-mil studies still, bc of the issue of what local vs distant forces are willing to do.
In theory, distant forces are more useful for oppressive tyrants bc they have no relationship w the locals and will ergo be happy to oppress them.

HOWEVER, the US history of domestic use of federal force is at least partly a story of the intervention of neutral federal forces in situations where local law enforcement/militia *were* the oppressors.

I’m fairly certain (though not far enough in my research to be 100% sure) that the persistence of this “the military can’t do law enforcement” narrative is actually a small part of the larger lost cause narrative, or a general anti-federalist stance.

Again: my point is NOT that there are no issues or problems w using the fedrl mil for law enforcement. Esp. As the military has become more specialized, there are all kinds of valid concerns. Point is that they absolutely are an available federal tool, and are so for a reason.

Anyway, I don’t mean to imply that I discovered something no one else knew - just that I’ve wondered for ages where this weird juxtaposition comes from, of fairly regular use of the mil for law enforcement, alongside a widespread popular narrative that Americans Don’t Do That.

On a separate point, remember how I said the 1877 labor strikes had something to do w Repub willingness to pass the PCA? There were a couple of issues involved there ...

For the Army, a big issue was confusing chains of command. Often, when they were called to help out, they weren’t sure whether they shld follow the orders of the local gov’t official, the local federal marshal, the Army chain of command, or what.

For the Army, the significance of the PCA was that it clarified chains of command. Local officials, even Marshals, couldn’t order them around; they took orders only from their own chain of command, going up to the Secy of War. The military very much appreciated this.

Also, PCA was a rider on the Army approps bill. Dems had tried for years to pass it as a rider, and Rs had resisted, but evtlly the pressure from multiple directions was enough that the Rs passed it.
I’m massively oversimplifying this story, but the approps aspect is important.

P.s. an astute reader said he’d been told the PCA forbade the mil from surveillance of US citizens on US soil and that I hadn’t mentioned it in my list of statutory constraints. That’s cuz my rsrch on domestic mil intel has been separate & I forgot : https://twitter.com/lindsaypcohn/status/1114191835348520960?s=21 https://twitter.com/lindsaypcohn/status/1114191835348520960