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Wednesday, February 28, 2018

Bump Stocks and Machine Guns as Case Study in Textualism, Chevron, and the Ambiguity of “Ambiguity”

Textualism in statutory interpretation is, on one view (which happens to be my own) a shiny, steely, precise knife blade with a handle made of silly putty. If the text is deemed to be “unambiguous,” then textualism seems to cleanly slice through obfuscation like a scalpel, cutting away all messy questions about how to define and apply broad statutory purpose, legislative history, or judicially crafted substantive canons by instructing the judge to follow the “plain” text. The blade of textualism, however, can be deployed only if the text is “unambiguous,” and unfortunately the concept of ambiguity is the most ambiguous concept of them all.

President Trump has recently provided us law profs with an interesting example of ambiguously ambiguous statutory language, suitable for in-class problems or final exams. (Whatever its merits as an effective presidency, the Trump Administration is a gift that keeps on giving to law profs teaching statutory interpretation). He has promised to ban “bump stocks” on firearms as a response to mass shootings in Parkland, Florida and Las Vegas, Nevada.

Putting aside the question of whether such a ban would produce any discernible reduction in gun deaths, does the President have the power to ban “bump stocks”? The question turns on the meaning of a six-word phrase in the National Firearms Act of 1934, a statute enacted during the national panic about Tommy-gun toting bank robbers and gangsters (e.g., “‘Machine Gun’ Kelly”). The phrase beautifully illustrates how ambiguity about ambiguity allows judges to turn Chevron and other substantive canons on and off like a spigot, all the while ostensibly adhering to the most rigorous textualism. After the jump, my thoughts on how “sliding scale” textualism might be a better way of resolving such meta-ambiguity than the grammar wars between majority and dissenting opinions now favored by SCOTUS. [Update: For an earlier formulation and much more precise and better-defended version of what I call “sliding scale” textualism, you should read Richard Re’s Green Bag essay The New Holy Trinity].

1. Why is the National Firearms Act is ambiguously ambiguous?

26 U.S.C. Section 5845(b) defines “machine gun” covered by the statute to mean

any weapon which shoots, is designed to shoot, or can be readily restored to shoot, automatically more than one shot, without manual reloading, by a single function of the trigger. The term shall also include the frame or receiver of any such weapon, any part designed and intended solely and exclusively, or combination of parts designed and intended, for use in converting a weapon into a machinegun....(emphasis added)

So is a “bump stock” “designed and intended” to convert a firearm into a “weapon which shoots...automatically more than one shot...by a single function of the trigger”? These devices use the recoil power of the gun to bounce (“bump”) the shooter’s finger repeatedly up against the trigger, allowing them to shoot faster than their finger’s muscular movements would normally allow. This finger-bumping action looks “automatic[]” (the shooter’s voluntary motions do not cause the trigger to be pulled). But does this bouncing mechanism constitute a “single function of the trigger”?

One can make a textual argument on either side of the question. Since each shot of a bump-stock-equipped weapon is accompanied by a corresponding pull on the trigger, one “plain text” answer might be “no”: “more than one shot...by a single function of the trigger” means that the ratio of trigger pulls to shots must be more than 1:1. On the other hand, it is that initial voluntary motion of the finger’s pulling the trigger that starts the initial recoil of the gun that, in turn, bounces one’s finger against the trigger involuntarily, thereby causing all of the subsequent recoils and bounces that lead to rapid discharge of the firearm. Why cannot that initial voluntarily induced motion of the trigger be deemed to be a “single function of the trigger” that causes the later involuntary trigger pulls leading to “more than one shot”?

In 2010, the ATF gave an opinion letter to Slide Fire, a firearms manufacturer, stating that bump stocks were not a machine gun conversion device within the meaning of the statute, because the device would not, by itself, “automatically” produce rapid fire. Instead, for the device to cause repeated trigger pulls, “the shooter must apply constant forward pressure with the non-shooting hands and constant rearward pressure with the shooting hand.”

Is the 2010 opinion letter persuasive? Again, one sinks into the Talmudic murk of ambiguously ambiguous text. The letter assumes that a device “shoots automatically more than one shot” only if the shooter makes no voluntary decisions whatsoever to insure that continuation of the automatic fire. One could argue, however, that this sort of reasoning proves too much. Machine guns normally will not fire unless the shooter applies constant pressure to the trigger: If one drops the machine gun, it does not ordinarily continue to spew bullets by itself. By extension of ATF’s reasoning, no weapon ever sold would constitute a “machine gun,” because all machine-gun triggers require the shooter to continue some sort of voluntary action for the shooting to continue.

The ATF’s letter suggests a response to this rejoinder: According to the letter, devices covered by the statute must have “automatically functioning mechanical parts or springs” to perform “an automatic mechanical function when installed.” Although the letter does not explain why this criterion is related to the statutory language, a smart lawyer might fill in the blanks: The gun “shoots automatically more than one shot” only if the statutorily required “single function of the trigger” contains an “automatic” component, and, in ordinary English, “automatic” components must have parts that move by themselves. The gun’s recoil is not part of the bump stock, which does not move by itself. No moving parts? No “automatic” function.

Shall we go one more round of this textualist style of reasoning? Against the ATF’s letter, one might ask why “automatically” should be read to modify “single function of the trigger.” In the statute’s text, “automatically” is an adverb modifying the verb “shoots,” not the noun “function.” But the ATF might reply that the canon noscitur a sociis requires that the noun “function” be read in light of nearby words like “automatically shoots,” suggesting that the device itself must move by itself — “automatically.”

In the wake of the Las Vegas mass shooting, the ATF issued an ANPRM requesting comments on whether it should revisit its 2010 interpretation. Within 30 days, ATF received over 100,000 comments on the question.

I am inclined to say that those competing comments as well as the rival arguments outlined above suggest that the statutory language is ambiguous enough for the ATF to invoke Chevron and reverse its 2010 letter ruling. But I would also concede that a SCOTUS inclined to engage in textual hair-splitting might determine that one set of textual arguments is better than the other and write that 2010 letter into statutory stone. As Yates and Lockhart Indicate, the existence of decent textual arguments on either side of a question does not suffice, in SCOTUS’s collective mind, to justify an inference of ambiguity.

The statute here, in sum, is ambiguously ambiguous. The SCOTUS could invoke Chevron or not, depending on how finely they want to weigh competing textualist arguments. And this leads to a second question, viz....

2. Why not use “sliding scale” textualism to resolve ambiguous ambiguity?

Why not determine whether statutory text is ambiguous by looking to the extra-textual purposes of a statute? As Will Baude and Ryan Doerfler incisively note in an elegant essay on the Plain Statement Rule, “a court’s perception of what Congress is trying to say depends in large part on that court’s understanding of what Congress is trying to do.” On this view, the courts ought to determine whether the NFA “unambiguously” excludes bump stocks from the definition of “machine guns” by looking into the purpose of federal regulation of machine guns. If the practical point of the statute was to place special federal controls on weapons that fire especially rapidly, then excluding the bump stock from the statute will seem odd. This practical purpose counts as a reason to weigh against the textual arguments for a narrow reading of statutory text. Even if that textual argument for a narrow reading is a little better than its rival textual argument for a broader reading, the purpose-based argument cancels out the former, at least to the extent of allowing the court to declare the statute ambiguous enough for the agency to make the final decision under Chevron.

On this “sliding scale” view of textualism, text and purpose are weighted on a single scale, with neither having absolute lexical priority over the other. Super-clear text might have priority over murky or unimportant purpose (see, e.g., United States v. Locke), but closely matched textual arguments might be “outweighed” by super-strong purpose-based arguments, even if one textual argument were slightly better than all rival textual readings. The sliding scale throws purpose into the mix of authorities right away, to be weighed alongside them at every stage of interpretation.

Such a “sliding scale” theory has the virtue of reflecting what courts actually do (albeit not what they say they do). It also provides a way to resolve conflicts among competing textual arguments other than the absurdity of balancing fly-specking textual minutiae while ignoring obvious statutory purpose. Against the objection that text reflects interest-group bargains that could run counter to the main thrust of a statute, there is the simple rejoinder: Maybe, but maybe not. If the textual arguments on either side of a question are reasonably closely balanced, then the slight superiority of one textual argument over its equally textual rival seems like a weird way to memorialize a legislative deal. After all, one would assume that the deal-makers would not want to codify their deal-making in language requiring a degree in linguistics or familiarity with some textual corpus stored at Brigham Young University. If Justice Kagan’s secret decoder ring yields an application of the “last antecedent rule” different from Justice Sotomayor’s, then it is time to throw in the towel on text, not parse every comma and romanette with the idea that somehow smuggled into the interstices of such arcana lies a bargain that lifted the veto gates of Congress. [Update #2: Ryan Doerfler’s High-Stakes Interpretation provides a powerful defense of the idea that the standards for finding semantic clarity should vary with the pragmatic stakes — a position that he defends by citing an overlapping consensus sounding in both sound semantic and pragmatic principles. I endorse Doerfler’s idea but am indifferent to its pedigree in semantics or pragmatics, since I tend to think that the distinction is of, well, merely semantic importance].

Posted by Rick Hills on February 28, 2018 at 10:56 AM | Permalink


I think you misunderstand the ATF's point and then draw a poor comparison.

Your point is that bump stocks rely on "involuntary" finger movement to repeatedly hit the trigger. The ATF's point is better stated as these finger movements are not "involuntary" since the shooter must constantly apply pressure. In addition, the non-trigger hand must constantly be pushing the firearm forward so that the trigger finger is always forced against the trigger. So think of it as a two-part movement. The forward hand must be pushing the weapon forward continuously (clearly a wholly voluntary action) while the trigger hand must be pressed back against the trigger. Thus, the trigger action isn't actually involuntary since you are using a second voluntary movement to force the weapon forward which makes the "bump fire" possible. Without both of these movements, the weapon does not "bump fire". This is not the case for a machine gun.

While bump stocks make this process easier, they are by no means necessary to the process. In short, one does not need a bump stock to actually "bump fire".

And interesting question is, assuming a ban on bump stocks, would bump firing without the stocks be legal?

Posted by: YesterdayIKilledAMammoth | Feb 28, 2018 11:39:48 AM

First, it's ambiguous whether you're ascribing "this view" to Baude and Doerfler, but I'm pretty sure that it isn't their view; their argument was that extratextual considerations are either illegitimate or not, not conditionally legitimate depending on whether the text is clear. They're probably much closer to thinking them illegitimate, though the paper doesn't argue that. The passage you quote is only describing judges' practice, not endorsing it.

Second, what you describe doesn't sound like a version of textualism *at all* to me. Purposivists conceded to us long ago that they were stuck with the text if it was "super-clear," and it doesn't sound like you're even willing to concede that much (super-clear text, you say, "might" (!) outweigh "murky" purposes); after that, you start weighing what the text barely ambiguously says against what "seems odd" to you. I would describe that as a mildly chastened purposivism of the sort that Breyer practices at times; see, e.g., his dissenting opinion in Jennings yesterday.

Third, if you do this approach seriously, and don't just dump the text in favor of purpose once the text turns out to be less than super-clear, you have the same exact problem of measuring ambiguity that you bemoan. Actually, it's worse. Textualists, even when faced with a strong ambiguity-resolving canon, only have to figure out (a) whether a statute is clear or not and (b), absent such a canon, whether the text weighs more in favor of one reading or another. Beyond that they don't have to precisely quantify if they're 55% confident in a reading, 67%, etc. But you, with your weighing of degrees of clarity against the strength of purposive arguments (which seem incommensurable to me with clarity -- I don't understand how I'm supposed to weigh how confident I feel that the definition of machine gun excludes bump stock-enhanced machine guns against how odd it seems that the statute doesn't cover them, any more than I know how to weigh how clear a statute is against how odd I find a piece of music), actually must have some rough sense of how clear a statute is, and have to answer questions like, "do the textual arguments for X only slightly outweigh the ones for Y, or comfortably -- short of unambiguity -- outweigh them?" Maybe your approach would make Chevron easier, as you could just deem virtually anything ambiguous, but I have no idea what your ambiguity threshold would be; a text that's a hair short of super-clear, outweighed by the apparent textual meaning seeming a little odd? How much oddity?

Fourth, it seems to me that legislative half-measures are overwhelmingly the only sorts of legislative measures we get, so it just doesn't seem odd at all to me that Congress would only ban the traditional sort of machine guns even though other contraptions can be rigged up to fire just as rapidly. Wasn't the assault-weapons ban riddled with loopholes? Can't it be fairly assumed that any gun-control measure Congress passes this year will fall absurdly short of its stated purposes?

Besides, did bump stocks even exist in 1934? If you're trying to precisely describe the sort of rapid-firing gun you want to ban without directly describing it in terms of rapidity, which would be difficult, and the kind that exists at the time is one that fires multiple shots with a single pull of the trigger, what's odd about failing to cover as-yet uninvented others? What you're talking about really sounds like an exercise in imaginative reconstruction; had Congress known in 1934 that devices would be invented that would mimic machine-gun fire without firing multiple shots upon a single pull of the trigger, would Congress want to ban them too? Maybe. Yet note that Congress hasn't banned bump stocks since they've entered the news, even though Congress (incoherently?) continues to think the machine-gun ban is a good idea and gun lobbyists don't even try to touch it.

Fifth, I think the statute is terribly clear. A "function" of the trigger is a pulling of the trigger; I just don't see what the argument would be that only voluntary functions count. On your suggested reading, a gun lacking a bump stock becomes a machine gun when operated by someone with a tremor in his hands, or at least it would but for "automatically."

Posted by: Asher Steinberg | Feb 28, 2018 12:28:05 PM

Here are six responses, Asher.

1. I am certainly not trying to ascribe “sliding scale” textualism to Will and Ryan: I am just adopting their snappy sentence about what judges actually do. They can speak for themselves. But...

2. I would note that, if judges persistently ignore in fact the High Theory of textualism by covertly thinking about a statute’s purposes in deciding whether the text is ambiguous, then maybe that theory is a lousy theory. Even a purely normative theory ought to prescribe a possible action: “Should” implies “could.” if judges’ decisions are really not driven by all of that comma parsing, then I am inclined to think that the theoretical demand that they ignore purpose in focusing on grammar is normatively as well as empirically bad theory.

3. The absurdity canon allows purpose to trump super-clear text, so my willingness to waive the latter in favor of statutory purpose is not an innovation but merely the current status quo,

4. The problem of measuring ambiguity remains, but the inquiry into resolving ambiguity moves away from what I regard as the absurdity of ignoring relevant evidence of meaning (what everyone understands the legislature to be aiming at) just because someone can make a slightly better textual argument about, say, the reference of a modifier.

5. I take the move away from lexically prior textualism to sliding scale textualism to better fulfill the goals of interpretation,because I take that goals to be giving (1) the legislature decent incentives to be clear in the text and (2) effect to the goals of the legislation as manifested in the usual ways (common sense, for instance). Giving reasonably clear text priority over reasonably clear purposes accomplishes this goal by rewarding legislators who embody purpose in text, given that one can usually make a plausible argument that the textual limits on statutory purpose served the purpose of compromise necessary for passage of the law. By contrast, where there are good-enough textual arguments on either side, it is implausible to view one side as better embodying the terms of a legislative deal just because one can come up with a hyper-refined view of grammar or diction under which one reading is better than the other.

Put another way, even if there are well-defined semantic norms pointing to one interpretation, giving absolute priority to those norms to the exclusion of pragmatic norms makes no sense as an approximation of how people actually communicate. Ordinary speakers frequently deviate slightly from semantic norms in any given sentence, relying on the apparent purpose of their utterance to clear up meaning. The division of meaning into two stages, a lexically prior semantic stage and a pragmatic stage that only clicks in when the semantics are unclear, is simply a misrepresentation of how we actually interpret, and speak to, each other. But this is certainly a topic for (at least) another blog post and perhaps an article.

6. We will just have to agree to disagree about the clarity of 26 U.S.C. Section 5845(b). if my eight paragraphs of argument does not persuade you, I guess I’ve failed in my mission!

Posted by: Rick Hills | Feb 28, 2018 1:01:28 PM

Interesting post, it must be considered in fact , that ,first : every legislation has a purpose . Second : it is not always that the purpose , is well expressed in the text , and finally : When the court faces an impasse ( not ambiguity necessarily , but impasse , since the court has a duty to prevail not to become linguistics ) it must consider among others , the purpose of the text or legislation , in order to overcome the impasse ( the paradox made by it ) . Here a very good illustration :

In the supreme court in Water Splach , Inc V. Menon , Alito has used it so ( dealing with the meaning of Article 10(a) , to the Hague service convention )here quoting :

(c) Three extratextual sources are especially helpful in ascertaining Article 10(a)’s meaning. First, the Convention’s drafting history strongly suggests that the drafters understood that service by postal channels was permissible.

End of quotation :

So , extratextual meanings or sources , must be brought in , and surly drafting history ( which tells the most about purpose ) . The point is , that the purpose , must be separated to two hierarchies :

The Subjective purpose ( the one expressed by legislator directly by him ) and the Objective one . The latter has to do with harmony of legislation , and objective values and principles ( like : equality , rule of law , due process etc..). The Objective one , must prevail , must take over the subjective generally speaking ( when facing another dilemma ) . This is because , the subjective one , has to do with the narrow intent of legislator , observing things in the past typically , but in time : Things change , must be re adopted to new reality ( like the appearance of Internet ) .


Posted by: El roam | Feb 28, 2018 1:04:37 PM

Just he who wants , can read some about the difference between Subjective and Objective purposes , in the book of prof Aharon Barak :

" Purposive Interpretation in Law "

Here certain abstract :

This book presents a comprehensive theory of legal interpretation, by a leading judge and legal theorist. Currently, legal philosophers and jurists apply different theories of interpretation to constitutions, statutes, rules, wills, and contracts. Aharon Barak argues that an alternative approach--purposive interpretation--allows jurists and scholars to approach all legal texts in a similar manner while remaining sensitive to the important differences. Moreover, regardless of whether purposive interpretation amounts to a unifying theory, it would still be superior to other methods of interpretation in tackling each kind of text separately.

Barak explains purposive interpretation as follows: All legal interpretation must start by establishing a range of semantic meanings for a given text, from which the legal meaning is then drawn. In purposive interpretation, the text's "purpose" is the criterion for establishing which of the semantic meanings yields the legal meaning. Establishing the ultimate purpose--and thus the legal meaning--depends on the relationship between the subjective and objective purposes; that is, between the original intent of the text's author and the intent of a reasonable author and of the legal system at the time of interpretation. This is easy to establish when the subjective and objective purposes coincide. But when they don't, the relative weight given to each purpose depends on the nature of the text. For example, subjective purpose is given substantial weight in interpreting a will; objective purpose, in interpreting a constitution.

Barak develops this theory with masterful scholarship and close attention to its practical application. Throughout, he contrasts his approach with that of textualists and neotextualists such as Antonin Scalia, pragmatists such as Richard Posner, and legal philosophers such as Ronald Dworkin. This book represents a profoundly important contribution to legal scholarship and a major alternative to interpretive approaches advanced by other leading figures in the judicial world.

Aharon Barak was president of the Supreme Court of Israel until his retirement in 2006. He is the author of Judicial Discretion, The Judge in a Democracy, numerous articles in English-language law journals, and several books in Hebrew. He is the winner of the 2006 Gruber Justice Prize from the Peter and Patricia Gruber Foundation. He is the author of Judicial Discretion (Yale), numerous articles in English-language law journals, and several books in Hebrew.

Can be found here :



Posted by: El roam | Feb 28, 2018 1:21:17 PM

The ruling mentioned , can be found here :



Posted by: El roam | Feb 28, 2018 1:39:20 PM

Fwiw, Will and I endorse that slogan as a normative matter as well as a positive one. That said, I don't think endorsing it entails anything about what *sources* courts should consider (though, in fairness to Asher, that passage goes on to talk about how a judge who does consider extra-textual sources would process them). What it does entail is that *whatever* sources courts consider, their linguistic assessment of statutory text inevitably involves consideration of apparent purpose. That's just what it means to say that "(statutory) language has meaning only in context," which is, we take it, common ground at this point.

Posted by: Ryan Doerfler | Feb 28, 2018 2:45:25 PM

Asher writes: "Purposivists conceded to us long ago that they were stuck with the text if it was 'super-clear...'"

I'm not sure this is right. If there are self-identified purposivists who believe it, they need to go back and take a 101 crash course in the philosophy of language. Lawyers and legal theorists have finally internalized a point philosophers have been making for decades now: semantic and pragmatic content are different things. To say a text is "super-clear" is not only ambiguous between semantic and pragmatic content, you need a substantive theory of law in order to vindicate the claim that on the basis of semantic content alone we can draw out legal effects (even textualists like John Manning don't insist upon this). And even if a text does not have indexicals or ellipses, its *meaning* is underdetermined by semantic content. For a text to be "super-clear" must thus always be a function from pragmatic enrichment of the kind purposivists should be happy to insist upon in every piece of legal text we confront.

Posted by: Sam | Feb 28, 2018 4:05:30 PM

For a law to be constitutional it must be the least-restrictive means necessary

"In considering this question, a court assumes that certain protected speech may be regulated, and then asks what is the least restrictive alternative that can be used to achieve that goal. The purpose of the test is not to consider whether the challenged restriction has some effect in achieving Congress’ goal, regardless of the restriction it imposes. The purpose of the test is to ensure that speech is restricted no further than necessary to achieve the goal, for it is important to assure that legitimate speech is not chilled or punished. For that reason, the test does not begin with the status quo of existing regulations, then ask whether the challenged restriction has some additional ability to achieve Congress’ legitimate interest. Any restriction on speech could be justified under that analysis. Instead, the court should ask whether the challenged regulation is the least restrictive means among available, effective alternatives."
-Ashcroft v. American Civil Liberties Union II, 2004

"For the First Amendment [6] does not speak equivocally. It prohibits any law "abridging the freedom of speech, or of the press." It must be taken as a command of the broadest scope that explicit language, read in the context of a liberty-loving society, will allow."
-Bridges v. California, 1941

If excise taxes on rights are unconstitutional (Grosjean v. American Press Co., Inc., Harper v. Virginia Board of Elections), if waiting periods are unconstitutional (Akron v. Akron), if being 21 is unconstitutional (26th Amendment)--then these are not the least-restrictive means. They would be unconstitutional for any other right, like voting or abortion, so they are unconstitutional for every right, like owning guns.

Posted by: Strict Scrutiny beats originalism | Feb 28, 2018 8:51:39 PM

"does the President have the power to ban “video games”? The question turns on the meaning of a six-word phrase in the National Firearms Act of 1934"

No, that's not how the first amendment works. If the first amendment prohibits Trump from banning video games, a law from 1934 can't give him the power to infringe the first amendment.

Of course you could argue that the copyright and patent clause doesn't apply to technology invented after 1791, and therefore the first amendment can't protect expression created with that technology. But that would defeat the entire purpose of allowing people to patent things if it only protected patents already in effect when the constitution was ratified.

The patent clause is only useful if it allows people to keep patenting new technology and the first amendment is only useful if it protects expression created with the mediums people are actually expressing themselves in.

Now it's possible that the amendments weren't meant to be useful, but then the same could be said about congress' powers in the first place--in which case there would be no need to limit those powers with the amendments.

Posted by: stick in mud | Mar 1, 2018 2:16:33 AM

"Why not determine whether statutory text is ambiguous by looking to the extra-textual purposes of a statute?"

If someone could prove to you beyond a reasonable doubt that the fourteenth amendment was not written with the purpose to legalize abortion, would you call for Roe v. Wade to be overturned? Or would you say that purpose is irrelevant?

Stated purpose is irrelevant.

"True, the Act's stated purpose is to protect academic freedom. La.Rev.Stat.Ann. § 17:286.2 (West 1982). This phrase might, in common parlance, be understood as referring to enhancing the freedom of teachers to teach what they will. The Court of Appeals, however, correctly concluded that the Act was not designed to further that goal."
-Edwards v. Aguillard, 1987

Posted by: Purpose and good-faith | Mar 1, 2018 4:39:44 AM

"The Court of Appeals wrote that a state law is “constitutional if: (1) it does not have the purpose or effect of placing a substantial obstacle in the path of a woman seeking an abortion of a nonviable fetus; and (2) it is reasonably related to (or designed to further) a legitimate state interest.”"
-Whole Woman's Health v. Hellerstedt, 2016

Does the gun-control law have the purpose or effect of placing a substantial obstacle in the path of a woman seeking to own a gun or carry one in public for self-defense?

Posted by: Read the law the same for all amendments | Mar 1, 2018 5:57:05 AM

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