(Slip Opinion)              OCTOBER TERM, 2018                                       1

                                       Syllabus

         NOTE: Where it is feasible, a syllabus (headnote) will be released, as is
       being done in connection with this case, at the time the opinion is issued.
       The syllabus constitutes no part of the opinion of the Court but has been
       prepared by the Reporter of Decisions for the convenience of the reader.
       See United States v. Detroit Timber & Lumber Co., 200 U. S. 321, 337.


SUPREME COURT OF THE UNITED STATES

                                       Syllabus

                   NEW PRIME INC. v. OLIVEIRA

CERTIORARI TO THE UNITED STATES COURT OF APPEALS FOR
                  THE FIRST CIRCUIT

    No. 17–340.     Argued October 3, 2018—Decided January 15, 2019
Petitioner New Prime Inc. is an interstate trucking company, and re-
  spondent Dominic Oliveira is one of its drivers. Mr. Oliveira works
  under an operating agreement that calls him an independent con-
  tractor and contains a mandatory arbitration provision. When Mr.
  Oliveira filed a class action alleging that New Prime denies its driv-
  ers lawful wages, New Prime asked the court to invoke its statutory
  authority under the Federal Arbitration Act to compel arbitration.
  Mr. Oliveira countered that the court lacked authority because §1 of
  the Act excepts from coverage disputes involving “contracts of em-
  ployment” of certain transportation workers. New Prime insisted
  that any question regarding §1’s applicability belonged to the arbitra-
  tor alone to resolve, or, assuming the court could address the ques-
  tion, that “contracts of employment” referred only to contracts that
  establish an employer-employee relationship and not to contracts
  with independent contractors. The District Court and First Circuit
  agreed with Mr. Oliveira.
Held:
    1. A court should determine whether a §1 exclusion applies before
 ordering arbitration. A court’s authority to compel arbitration under
 the Act does not extend to all private contracts, no matter how em-
 phatically they may express a preference for arbitration. Instead, an-
 tecedent statutory provisions limit the scope of a court’s §§3 and 4
 powers to stay litigation and compel arbitration “accord[ing to] the
 terms” of the parties’ agreement. Section 2 provides that the Act ap-
 plies only when the agreement is set forth as “a written provision in
 any maritime transaction or a contract evidencing a transaction in-
 volving commerce.” And §1 helps define §2’s terms, warning, as rele-
 vant here, that “nothing” in the Act “shall apply” to “contracts of em-
2                    NEW PRIME INC. v. OLIVEIRA

                                  Syllabus

    ployment of seamen, railroad employees, or any other class of work-
    ers engaged in foreign or interstate commerce.” For a court to invoke
    its statutory authority under §§3 and 4, it must first know if the par-
    ties’ agreement is excluded from the Act’s coverage by the terms of
    §§1 and 2. This sequencing is significant. See, e.g., Bernhardt v. Pol-
    ygraphic Co. of America, 350 U. S. 198, 201–202. New Prime notes
    that the parties’ contract contains a “delegation clause,” giving the
    arbitrator authority to decide threshold questions of arbitrability,
    and that the “severability principle” requires that both sides take all
    their disputes to arbitration. But a delegation clause is merely a spe-
    cialized type of arbitration agreement and is enforceable under §§3
    and 4 only if it appears in a contract consistent with §2 that does not
    trigger §1’s exception. And, the Act’s severability principle applies
    only if the parties’ arbitration agreement appears in a contract that
    falls within the field §§1 and 2 describe. Pp. 3–6.
       2. Because the Act’s term “contract of employment” refers to any
    agreement to perform work, Mr. Oliveira’s agreement with New
    Prime falls within §1’s exception. Pp. 6–15.
          (a) “[I]t’s a ‘fundamental canon of statutory construction’ that
    words generally should be ‘interpreted as taking their ordinary . . .
    meaning . . . at the time Congress enacted the statute.’ ” Wisconsin
    Central Ltd. v. United States, 585 U. S. ___, ___ (quoting Perrin v.
    United States, 444 U. S. 37, 42). After all, if judges could freely in-
    vest old statutory terms with new meanings, this Court would risk
    amending legislation outside the “single, finely wrought and exhaust-
    ively considered, procedure” the Constitution commands. INS v.
    Chadha, 462 U. S. 919, 951. The Court would risk, too, upsetting re-
    liance interests by subjecting people today to different rules than
    they enjoyed when the statute was passed. At the time of the Act’s
    adoption in 1925, the phrase “contract of employment” was not a
    term of art, and dictionaries tended to treat “employment” more or
    less as a synonym for “work.” Contemporaneous legal authorities
    provide no evidence that a “contract of employment” necessarily sig-
    naled a formal employer-employee relationship. Evidence that Con-
    gress used the term “contracts of employment” broadly can be found
    in its choice of the neighboring term “workers,” a term that easily
    embraces independent contractors. Pp. 6–10.
          (b) New Prime argues that by 1925, the words “employee” and
    “independent contractor” had already assumed distinct meanings.
    But while the words “employee” and “employment” may share a
    common root and intertwined history, they also developed at different
    times and in at least some different ways. The evidence remains
    that, as dominantly understood in 1925, a “contract of employment”
    did not necessarily imply the existence of an employer-employee rela-
                     Cite as: 586 U. S. ____ (2019)                     3

                                Syllabus

  tionship. New Prime’s argument that early 20th-century courts
  sometimes used the phrase “contracts of employment” to describe
  what are recognized today as agreements between employers and
  employees does nothing to negate the possibility that the term also
  embraced agreements by independent contractors to perform work.
  And its effort to explain away the statute’s suggestive use of the term
  “worker” by noting that the neighboring terms “seamen” and “rail-
  road employees” included only employees in 1925 rests on a precari-
  ous premise. The evidence suggests that even “seamen” and “railroad
  employees” could be independent contractors at the time the Arbitra-
  tion Act passed. Left to appeal to the Act’s policy, New Prime sug-
  gests that this Court order arbitration to abide Congress’ effort to
  counteract judicial hostility to arbitration and establish a favorable
  federal policy toward arbitration agreements. Courts, however, are
  not free to pave over bumpy statutory texts in the name of more ex-
  peditiously advancing a policy goal. Rather, the Court should respect
  “the limits up to which Congress was prepared” to go when adopting
  the Arbitration Act. United States v. Sisson, 399 U. S. 267, 298. This
  Court also declines to address New Prime’s suggestion that it order
  arbitration anyway under its inherent authority to stay litigation in
  favor of an alternative dispute resolution mechanism of the parties’
  choosing. Pp. 10–15.
857 F. 3d 7, affirmed.

  GORSUCH, J., delivered the opinion of the Court, in which all other
Members joined, except KAVANAUGH, J., who took no part in the consid-
eration or decision of the case. GINSBURG, J., filed a concurring opinion.
                        Cite as: 586 U. S. ____ (2019)                              1

                             Opinion of the Court

     NOTICE: This opinion is subject to formal revision before publication in the
     preliminary print of the United States Reports. Readers are requested to
     notify the Reporter of Decisions, Supreme Court of the United States, Wash-
     ington, D. C. 20543, of any typographical or other formal errors, in order
     that corrections may be made before the preliminary print goes to press.


SUPREME COURT OF THE UNITED STATES
                                   _________________

                                   No. 17–340
                                   _________________


              NEW PRIME INC., PETITIONER v.
                   DOMINIC OLIVEIRA
 ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF
             APPEALS FOR THE FIRST CIRCUIT
                               [January 15, 2019]

  JUSTICE GORSUCH delivered the opinion of the Court.
  The Federal Arbitration Act requires courts to enforce
private arbitration agreements. But like most laws, this one
bears its qualifications. Among other things, §1 says that
“nothing herein” may be used to compel arbitration in dis-
putes involving the “contracts of employment” of certain
transportation workers. 9 U. S. C. §1. And that qualification
has sparked these questions: When a contract delegates
questions of arbitrability to an arbitrator, must a court leave
disputes over the application of §1’s exception for the arbitra-
tor to resolve? And does the term “contracts of employment”
refer only to contracts between employers and employees, or
does it also reach contracts with independent contractors?
Because courts across the country have disagreed on the
answers to these questions, we took this case to resolve
them.
                            I
  New Prime is an interstate trucking company and Dom-
inic Oliveira works as one of its drivers. But, at least on
paper, Mr. Oliveira isn’t an employee; the parties’ con-
tracts label him an independent contractor. Those agree-
2                NEW PRIME INC. v. OLIVEIRA

                      Opinion of the Court

ments also instruct that any disputes arising out of the
parties’ relationship should be resolved by an arbitrator—
even disputes over the scope of the arbitrator’s authority.
   Eventually, of course, a dispute did arise. In a class action
lawsuit in federal court, Mr. Oliveira argued that New Prime
denies its drivers lawful wages. The company may call its
drivers independent contractors. But, Mr. Oliveira alleged,
in reality New Prime treats them as employees and fails to
pay the statutorily due minimum wage. In response to Mr.
Oliveira’s complaint, New Prime asked the court to invoke
its statutory authority under the Act and compel arbitration
according to the terms found in the parties’ agreements.
   That request led to more than a little litigation of its
own. Even when the parties’ contracts mandate arbitra-
tion, Mr. Oliveira observed, the Act doesn’t always author-
ize a court to enter an order compelling it. In particular,
§1 carves out from the Act’s coverage “contracts of em-
ployment of . . . workers engaged in foreign or interstate
commerce.” And at least for purposes of this collateral
dispute, Mr. Oliveira submitted, it doesn’t matter whether
you view him as an employee or independent contractor.
Either way, his agreement to drive trucks for New Prime
qualifies as a “contract[ ] of employment of . . . [a] worker[ ]
engaged in . . . interstate commerce.” Accordingly, Mr.
Oliveira argued, the Act supplied the district court with no
authority to compel arbitration in this case.
   Naturally, New Prime disagreed. Given the extraordi-
nary breadth of the parties’ arbitration agreement, the
company insisted that any question about §1’s application
belonged for the arbitrator alone to resolve. Alternatively
and assuming a court could address the question, New
Prime contended that the term “contracts of employment”
refers only to contracts that establish an employer-
employee relationship. And because Mr. Oliveira is, in
fact as well as form, an independent contractor, the com-
pany argued, §1’s exception doesn’t apply; the rest of the
                 Cite as: 586 U. S. ____ (2019)            3

                     Opinion of the Court

statute does; and the district court was (once again) re-
quired to order arbitration.
  Ultimately, the district court and the First Circuit sided
with Mr. Oliveira. 857 F. 3d 7 (2017). The court of ap-
peals held, first, that in disputes like this a court should
resolve whether the parties’ contract falls within the Act’s
ambit or §1’s exclusion before invoking the statute’s au-
thority to order arbitration. Second, the court of appeals
held that §1’s exclusion of certain “contracts of employ-
ment” removes from the Act’s coverage not only employer-
employee contracts but also contracts involving independ-
ent contractors. So under any account of the parties’
agreement in this case, the court held, it lacked authority
under the Act to order arbitration.
                              II
  In approaching the first question for ourselves, one
thing becomes clear immediately. While a court’s authority
under the Arbitration Act to compel arbitration may be
considerable, it isn’t unconditional. If two parties agree to
arbitrate future disputes between them and one side later
seeks to evade the deal, §§3 and 4 of the Act often require
a court to stay litigation and compel arbitration
“accord[ing to] the terms” of the parties’ agreement. But
this authority doesn’t extend to all private contracts, no
matter how emphatically they may express a preference for
arbitration.
  Instead, antecedent statutory provisions limit the scope
of the court’s powers under §§3 and 4. Section 2 provides
that the Act applies only when the parties’ agreement to
arbitrate is set forth as a “written provision in any mari-
time transaction or a contract evidencing a transaction
involving commerce.” And §1 helps define §2’s terms.
Most relevant for our purposes, §1 warns that “nothing” in
the Act “shall apply” to “contracts of employment of sea-
men, railroad employees, or any other class of workers
4               NEW PRIME INC. v. OLIVEIRA

                     Opinion of the Court

engaged in foreign or interstate commerce.” Why this very
particular qualification? By the time it adopted the Arbi-
tration Act in 1925, Congress had already prescribed
alternative employment dispute resolution regimes for
many transportation workers. And it seems Congress “did
not wish to unsettle” those arrangements in favor of what-
ever arbitration procedures the parties’ private contracts
might happen to contemplate. Circuit City Stores, Inc. v.
Adams, 532 U. S. 105, 121 (2001).
   Given the statute’s terms and sequencing, we agree with
the First Circuit that a court should decide for itself
whether §1’s “contracts of employment” exclusion applies
before ordering arbitration. After all, to invoke its statu-
tory powers under §§3 and 4 to stay litigation and compel
arbitration according to a contract’s terms, a court must
first know whether the contract itself falls within or be-
yond the boundaries of §§1 and 2. The parties’ private
agreement may be crystal clear and require arbitration of
every question under the sun, but that does not necessarily
mean the Act authorizes a court to stay litigation and send
the parties to an arbitral forum.
   Nothing in our holding on this score should come as a
surprise. We’ve long stressed the significance of the stat-
ute’s sequencing. In Bernhardt v. Polygraphic Co. of
America, 350 U. S. 198, 201–202 (1956), we recognized
that “Sections 1, 2, and 3 [and 4] are integral parts of a
whole. . . . [Sections] 1 and 2 define the field in which
Congress was legislating,” and §§3 and 4 apply only to
contracts covered by those provisions. In Circuit City, we
acknowledged that “Section 1 exempts from the [Act] . . .
contracts of employment of transportation workers.” 532
U. S., at 119. And in Southland Corp. v. Keating, 465
U. S. 1, 10–11, and n. 5 (1984), we noted that “the enforce-
ability of arbitration provisions” under §§3 and 4 depends
on whether those provisions are “part of a written mari-
time contract or a contract ‘evidencing a transaction in-
                 Cite as: 586 U. S. ____ (2019)           5

                     Opinion of the Court

volving commerce’ ” under §2—which, in turn, depends on
the application of §1’s exception for certain “contracts of
employment.”
  To be sure, New Prime resists this straightforward
understanding. The company argues that an arbitrator
should resolve any dispute over §1’s application because of
the “delegation clause” in the parties’ contract and what is
sometimes called the “severability principle.” A delegation
clause gives an arbitrator authority to decide even the
initial question whether the parties’ dispute is subject to
arbitration. Rent-A-Center, West, Inc. v. Jackson, 561
U. S. 63, 68–69 (2010). And under the severability princi-
ple, we treat a challenge to the validity of an arbitration
agreement (or a delegation clause) separately from a
challenge to the validity of the entire contract in which it
appears. Id., at 70–71. Unless a party specifically chal-
lenges the validity of the agreement to arbitrate, both
sides may be required to take all their disputes—including
disputes about the validity of their broader contract—to
arbitration. Ibid. Applying these principles to this case,
New Prime notes that Mr. Oliveira has not specifically
challenged the parties’ delegation clause and submits that
any controversy should therefore proceed only and imme-
diately before an arbitrator.
  But all this overlooks the necessarily antecedent statu-
tory inquiry we’ve just discussed. A delegation clause is
merely a specialized type of arbitration agreement, and
the Act “operates on this additional arbitration agreement
just as it does on any other.” Id., at 70. So a court may
use §§3 and 4 to enforce a delegation clause only if the
clause appears in a “written provision in . . . a contract
evidencing a transaction involving commerce” consistent
with §2. And only if the contract in which the clause
appears doesn’t trigger §1’s “contracts of employment”
exception. In exactly the same way, the Act’s severability
principle applies only if the parties’ arbitration agreement
6               NEW PRIME INC. v. OLIVEIRA

                     Opinion of the Court

appears in a contract that falls within the field §§1 and 2
describe. We acknowledged as much some time ago, ex-
plaining that, before invoking the severability principle, a
court should “determine[ ] that the contract in question is
within the coverage of the Arbitration Act.” Prima Paint
Corp. v. Flood & Conklin Mfg. Co., 388 U. S. 395, 402
(1967).
                              III
   That takes us to the second question: Did the First
Circuit correctly resolve the merits of the §1 challenge in
this case? Recall that §1 excludes from the Act’s compass
“contracts of employment of . . . workers engaged in . . .
interstate commerce.” Happily, everyone before us agrees
that Mr. Oliveira qualifies as a “worker[ ] engaged in . . .
interstate commerce.” For purposes of this appeal, too,
Mr. Oliveira is willing to assume (but not grant) that his
contracts with New Prime establish only an independent
contractor relationship.
   With that, the disputed question comes into clear view:
What does the term “contracts of employment” mean? If it
refers only to contracts that reflect an employer-employee
relationship, then §1’s exception is irrelevant and a court
is free to order arbitration, just as New Prime urges. But
if the term also encompasses contracts that require an
independent contractor to perform work, then the excep-
tion takes hold and a court lacks authority under the Act
to order arbitration, exactly as Mr. Oliveira argues.
                               A
   In taking up this question, we bear an important cau-
tion in mind. “[I]t’s a ‘fundamental canon of statutory
construction’ that words generally should be ‘interpreted
as taking their ordinary . . . meaning . . . at the time Con-
gress enacted the statute.’ ” Wisconsin Central Ltd. v.
United States, 585 U. S. ___, ___ (2018) (slip op., at 9)
                 Cite as: 586 U. S. ____ (2019)            7

                     Opinion of the Court

(quoting Perrin v. United States, 444 U. S. 37, 42 (1979)).
See also Sandifer v. United States Steel Corp., 571 U. S.
220, 227 (2014). After all, if judges could freely invest old
statutory terms with new meanings, we would risk
amending legislation outside the “single, finely wrought
and exhaustively considered, procedure” the Constitution
commands. INS v. Chadha, 462 U. S. 919, 951 (1983). We
would risk, too, upsetting reliance interests in the settled
meaning of a statute. Cf. 2B N. Singer & J. Singer, Suth-
erland on Statutes and Statutory Construction §56A:3
(rev. 7th ed. 2012). Of course, statutes may sometimes
refer to an external source of law and fairly warn readers
that they must abide that external source of law, later
amendments and modifications included. Id., §51:8 (dis-
cussing the reference canon). But nothing like that exists
here. Nor has anyone suggested any other appropriate
reason that might allow us to depart from the original
meaning of the statute at hand.
  That, we think, holds the key to the case. To many law-
yerly ears today, the term “contracts of employment” might
call to mind only agreements between employers and em-
ployees (or what the common law sometimes called masters
and servants). Suggestively, at least one recently published
law dictionary defines the word “employment” to mean “the
relationship between master and servant.” Black’s Law
Dictionary 641 (10th ed. 2014). But this modern intuition
isn’t easily squared with evidence of the term’s meaning at
the time of the Act’s adoption in 1925. At that time, a “con-
tract of employment” usually meant nothing more than an
agreement to perform work. As a result, most people then
would have understood §1 to exclude not only agreements
between employers and employees but also agreements that
require independent contractors to perform work.
  What’s the evidence to support this conclusion? It turns
out that in 1925 the term “contract of employment” wasn’t
defined in any of the (many) popular or legal dictionaries
8                  NEW PRIME INC. v. OLIVEIRA

                         Opinion of the Court

the parties cite to us. And surely that’s a first hint the
phrase wasn’t then a term of art bearing some specialized
meaning. It turns out, too, that the dictionaries of the era
consistently afforded the word “employment” a broad
construction, broader than may be often found in diction-
aries today. Back then, dictionaries tended to treat “em-
ployment” more or less as a synonym for “work.” Nor did
they distinguish between different kinds of work or work-
ers: All work was treated as employment, whether or not
the common law criteria for a master-servant relationship
happened to be satisfied.1
  What the dictionaries suggest, legal authorities confirm.
This Court’s early 20th-century cases used the phrase “con-
tract of employment” to describe work agreements involving
independent contractors.2 Many state court cases did the
same.3 So did a variety of federal statutes.4 And state stat-
——————
   1 See, e.g., 3 J. Murray, A New English Dictionary on Historical

Principles 130 (1891) (defining “employment” as, among other things,
“[t]he action or process of employing; the state of being employed.
The service (of a person). That on which (one) is employed; business;
occupation; a special errand or commission. A person’s regular
occupation or business; a trade or profession”); 3 The Century Dic-
tionary and Cyclopedia 1904 (1914) (defining “employment” as “[w]ork
or business of any kind”); W. Harris, Webster’s New International
Dictionary 718 (1st ed. 1909) (listing “work” as a synonym for “em-
ployment”); Webster’s Collegiate Dictionary 329 (3d ed. 1916) (same);
Black’s Law Dictionary 422 (2d ed. 1910) (“an engagement or render-
ing services” for oneself or another); 3 Oxford English Dictionary 130
(1933) (“[t]hat on which (one) is employed; business; occupation; a
special errand or commission”).
   2 See, e.g., Watkins v. Sedberry, 261 U. S. 571, 575 (1923) (agree-

ment between trustee and attorney to recover bankrupt’s property);
Owen v. Dudley & Michener, 217 U. S. 488, 494 (1910) (agreement
between Indian tribe and attorneys to pursue claims).
   3 See, e.g., Lindsay v. McCaslin (Two Cases), 123 Me. 197, 200, 122

A. 412, 413 (1923) (“When the contract of employment has been
reduced to writing, the question whether the person employed was an
independent contractor or merely a servant is determined by the court
as a matter of law”); Tankersley v. Webster, 116 Okla. 208, 210, 243 P.
                     Cite as: 586 U. S. ____ (2019)                   9

                         Opinion of the Court

utes too.5 We see here no evidence that a “contract of em-
ployment” necessarily signaled a formal employer-employee
or master-servant relationship.
   More confirmation yet comes from a neighboring term
in the statutory text. Recall that the Act excludes from
its coverage “contracts of employment of . . . any . . . class
of workers engaged in foreign or interstate commerce.” 9
U. S. C. §1 (emphasis added). Notice Congress didn’t use
the word “employees” or “servants,” the natural choices if
——————
745, 747 (1925) (“[T]he contract of employment between Tankersley
and Casey was admitted in evidence without objections, and we think
conclusively shows that Casey was an independent contractor”);
Waldron v. Garland Pocahontas Coal Co., 89 W. Va. 426, 427, 109
S. E. 729 (1921) (syllabus) (“Whether a person performing work for
another is an independent contractor depends upon a consideration of
the contract of employment, the nature of the business, the circum-
stances under which the contract was made and the work was done”);
see also App. to Brief for Respondent 1a–12a (citing additional
examples).
   4 See, e.g., Act of Mar. 19, 1924, ch. 70, §5, 43 Stat. 28 (limiting

payment of fees to attorneys “employed” by the Cherokee Tribe to
litigate claims against the United States to those “stipulated in the
contract of employment”); Act of June 7, 1924, ch. 300, §§2, 5, 43 Stat.
537–538 (providing same for Choctaw and Chickasaw Tribes); Act of
Aug. 24, 1921, ch. 89, 42 Stat. 192 (providing that no funds may be
used to compensate “any attorney, regular or special, for the United
States Shipping Board or the United States Shipping Board Emer-
gency Fleet Corporation unless the contract of employment has been
approved by the Attorney General of the United States”). See also
App. to Brief for Respondent 13a (citing additional examples).
   5 See, e.g., Act of Mar. 10, 1909, ch. 70, §1, 1909 Kan. Sess. Laws

p. 121 (referring to “contracts of employment of auditors, accountants,
engineers, attorneys, counselors and architects for any special pur-
pose”); Act of Mar. 4, 1909, ch. 4, §4, 1909 Okla. Sess. Laws p. 118
(“Should the amount of the attorney’s fee be agreed upon in the
contract of employment, then such attorney’s lien and cause of action
against such adverse party shall be for the amount so agreed upon”);
Act of Mar. 4, 1924, ch. 88, §1, 1924 Va. Acts ch. 91 (allowing exten-
sion of “contracts of employment” between the state and contractors
with respect to the labor of prisoners); App. to Brief for Respondent
14a–15a (citing additional examples).
10                 NEW PRIME INC. v. OLIVEIRA

                         Opinion of the Court

the term “contracts of employment” addressed them
alone. Instead, Congress spoke of “workers,” a term that
everyone agrees easily embraces independent contrac-
tors. That word choice may not mean everything, but it
does supply further evidence still that Congress used the
term “contracts of employment” in a broad sense to cap-
ture any contract for the performance of work by workers.
                              B
   What does New Prime have to say about the case build-
ing against it? Mainly, it seeks to shift the debate from
the term “contracts of employment” to the word “employee.”
Today, the company emphasizes, the law often distin-
guishes between employees and independent contractors.
Employees are generally understood as those who work “in
the service of another person (the employer) under an
express or implied contract of hire, under which the em-
ployer has the right to control the details of work perform-
ance.” Black’s Law Dictionary, at 639. Meanwhile,
independent contractors are sometimes described as those
“entrusted to undertake a specific project but who [are]
left free to do the assigned work and to choose the method
for accomplishing it.” Id., at 888. New Prime argues that,
by 1925, the words “employee” and “independent contrac-
tor” had already assumed these distinct meanings.6 And
given that, the company contends, the phrase “contracts of
employment” should be understood to refer only to rela-
tionships between employers and employees.
   Unsurprisingly, Mr. Oliveira disagrees. He replies that,
while the term “employment” dates back many centuries,
the word “employee” only made its first appearance in
English in the 1800s. See Oxford English Dictionary (3d
ed., Mar. 2014), www.oed.com/view/Entry/61374 (all In-

——————
 6 See, e.g., Atlantic Transp. Co. v. Coneys, 82 F. 177, 178 (CA2 1897);

Nyback v. Champagne Lumber Co., 109 F. 732, 741 (CA7 1901).
                       Cite as: 586 U. S. ____ (2019)                         11

                            Opinion of the Court

ternet materials as last visited Jan. 9, 2019). At that
time, the word from which it derived, “employ,” simply
meant to “apply (a thing) to some definite purpose.” 3 J.
Murray, A New English Dictionary on Historical Princi-
ples 129 (1891). And even in 1910, Black’s Law Dictionary
reported that the term “employee” had only “become
somewhat naturalized in our language.” Black’s Law
Dictionary 421 (2d ed. 1910).
   Still, the parties do share some common ground. They
agree that the word “employee” eventually came into wide
circulation and came to denote those who work for a wage
at the direction of another. They agree, too, that all this
came to pass in part because the word “employee” didn’t
suffer from the same “historical baggage” of the older
common law term “servant,” and because it proved useful
when drafting legislation to regulate burgeoning indus-
tries and their labor forces in the early 20th century.7 The
parties even agree that the development of the term “em-
ployee” may have come to influence and narrow our un-
derstanding of the word “employment” in comparatively
recent years and may be why today it might signify to
some a “relationship between master and servant.”8
——————
    7 See Carlson, Why the Law Still Can’t Tell an Employee When It

Sees One and How It Ought To Stop Trying, 22 Berkeley J. Emp. &
Lab. L. 295, 309 (2001) (discussing the “historical baggage” of the term
“servant”); Broden, General Rules Determining the Employment
Relationship Under Social Security Laws: After Twenty Years an
Unsolved Problem, 33 Temp. L. Q. 307, 327 (1960) (describing use of
the term “employer-employee,” in contradistinction to “master-servant,”
in the Social Security laws). Legislators searched to find a term that
fully encompassed the broad protections they sought to provide and
considered an “assortment of vague and uncertain terms,” including
“ ‘servant,’ . . . ‘employee,’ . . . ‘workman,’ ‘laborer,’ ‘wage earner,’ ‘opera-
tive,’ or ‘hireling.’ ” Carlson, 22 Berkeley J. Emp. & Lab. L., at 308.
Eventually “ ‘employee’ prevailed, if only by default, and the choice was
confirmed by the next wave of protective legislation—workers’ compen-
sation laws in the early years of the Twentieth Century.” Id., at 309.
    8 Black’s Law Dictionary 641 (10th ed. 2014); see also P. Durkin, Re-
12                 NEW PRIME INC. v. OLIVEIRA

                         Opinion of the Court

  But if the parties’ extended etymological debate per-
suades us of anything, it is that care is called for. The
words “employee” and “employment” may share a common
root and an intertwined history. But they also developed
at different times and in at least some different ways. The
only question in this case concerns the meaning of the
term “contracts of employment” in 1925. And, whatever
the word “employee” may have meant at that time, and
however it may have later influenced the meaning of
“employment,” the evidence before us remains that, as
dominantly understood in 1925, a contract of employment
did not necessarily imply the existence of an employer-
employee or master-servant relationship.
  When New Prime finally turns its attention to the term
in dispute, it directs us to Coppage v. Kansas, 236 U. S. 1,
13 (1915). There and in other cases like it, New Prime
notes, courts sometimes used the phrase “contracts of
employment” to describe what today we’d recognize as
agreements between employers and employees. But this
proves little. No one doubts that employer-employee
agreements to perform work qualified as “contracts of
employment” in 1925—and documenting that fact does
nothing to negate the possibility that “contracts of em-
ployment” also embraced agreements by independent
contractors to perform work. Coming a bit closer to
the mark, New Prime eventually cites a handful of early
20th-century legal materials that seem to use the term
“contracts of employment” to refer exclusively to employer-
employee agreements.9 But from the record amassed
——————
lease Notes: The Changes in Empathy, Employ, and Empire (Mar. 13,
2014) (“Over time” the meaning of several employ-related words have
“reflect[ed] changes in the world of work” and their meaning “shows an
increasingly marked narrowing”), online at https://public.oed.com/blog/
march-2014-update-release-notes/.
  9 See, e.g., 1 T. Conyngton, Business Law: A Working Manual of

Every-day Law 302–303 (2d ed. 1920); Newland v. Bear, 218 App. Div.
                     Cite as: 586 U. S. ____ (2019)                   13

                          Opinion of the Court

before us, these authorities appear to represent at most
the vanguard, not the main body, of contemporaneous
usage.
   New Prime’s effort to explain away the statute’s sugges-
tive use of the term “worker” proves no more compelling.
The company reminds us that the statute excludes “con-
tracts of employment” for “seamen” and “railroad employ-
ees” as well as other transportation workers. And because
“seamen” and “railroad employees” included only employ-
ees in 1925, the company reasons, we should understand
“any other class of workers engaged in . . . interstate
commerce” to bear a similar construction. But this argu-
ment rests on a precarious premise. At the time of the
Act’s passage, shipboard surgeons who tended injured
sailors were considered “seamen” though they likely
served in an independent contractor capacity.10 Even the
term “railroad employees” may have swept more broadly
at the time of the Act’s passage than might seem obvious
today. In 1922, for example, the Railroad Labor Board
interpreted the word “employee” in the Transportation Act
of 1920 to refer to anyone “engaged in the customary work
directly contributory to the operation of the railroads.”11
And the Erdman Act, a statute enacted to address disrup-
tive railroad strikes at the end of the 19th century, seems
to evince an equally broad understanding of “railroad

——————
308, 309, 218 N. Y. S. 81, 81–82 (1926); Anderson v. State Indus.
Accident Comm’n, 107 Ore. 304, 311–312, 215 P. 582, 583, 585 (1923);
N. Dosker, Manual of Compensation Law: State and Federal 8 (1917).
  10 See, e.g., The Sea Lark, 14 F. 2d 201 (WD Wash. 1926); The Buena

Ventura, 243 F. 797, 799 (SDNY 1916); Holt v. Cummings, 102 Pa. 212,
215 (1883); Allan v. State S. S. Co., 132 N. Y. 91, 99, 30 N. E. 482, 485
(1892) (“The work which the physician does after the vessel starts on
the voyage is his and not the ship owner’s”).
  11 Transportation Act of 1920, §§304, 307, 41 Stat. 456; Railway Em-

ployees’ Dept., A. F. of L. v. Indiana Harbor Belt R. Co., Decision No.
982, 3 R. L. B. 332, 337 (1922).
14                 NEW PRIME INC. v. OLIVEIRA

                         Opinion of the Court

employees.”12
   Unable to squeeze more from the statute’s text, New
Prime is left to appeal to its policy. This Court has said
that Congress adopted the Arbitration Act in an effort to
counteract judicial hostility to arbitration and establish “a
liberal federal policy favoring arbitration agreements.”
Moses H. Cone Memorial Hospital v. Mercury Constr.
Corp., 460 U. S. 1, 24 (1983). To abide that policy, New
Prime suggests, we must order arbitration according to
the terms of the parties’ agreement. But often and by
design it is “hard-fought compromise[ ],” not cold logic,
that supplies the solvent needed for a bill to survive the
legislative process. Board of Governors, FRS v. Dimension
Financial Corp., 474 U. S. 361, 374 (1986). If courts felt
free to pave over bumpy statutory texts in the name of
more expeditiously advancing a policy goal, we would risk
failing to “tak[e] . . . account of ” legislative compromises
essential to a law’s passage and, in that way, thwart
rather than honor “the effectuation of congressional in-
tent.” Ibid. By respecting the qualifications of §1 today,
we “respect the limits up to which Congress was prepared”
to go when adopting the Arbitration Act. United States v.
Sisson, 399 U. S. 267, 298 (1970).
   Finally, and stretching in a different direction entirely,
New Prime invites us to look beyond the Act. Even if the
statute doesn’t supply judges with the power to compel
arbitration in this case, the company says we should order
it anyway because courts always enjoy the inherent au-
——————
  12 The  Act provided for arbitration between railroads and workers,
and defined “employees” as “all persons actually engaged in any capacity
in train operation or train service of any description.” Act of June 1,
1898, ch. 370, 30 Stat. 424. The Act also specified that the railroads
would “be responsible for the acts and defaults of such employees in the
same manner and to the same extent as if . . . said employees [were]
directly employed by it.” Id., at 425. See Dempsey, Transportation: A
Legal History, 30 Transp. L. J. 235, 273 (2003).
                 Cite as: 586 U. S. ____ (2019)           15

                     Opinion of the Court

thority to stay litigation in favor of an alternative dispute
resolution mechanism of the parties’ choosing. That,
though, is an argument we decline to tangle with. The
courts below did not address it and we granted certiorari
only to resolve existing confusion about the application of
the Arbitration Act, not to explore other potential avenues
for reaching a destination it does not.
                                *
  When Congress enacted the Arbitration Act in 1925, the
term “contracts of employment” referred to agreements to
perform work. No less than those who came before him,
Mr. Oliveira is entitled to the benefit of that same under-
standing today. Accordingly, his agreement with New
Prime falls within §1’s exception, the court of appeals was
correct that it lacked authority under the Act to order
arbitration, and the judgment is
                                                   Affirmed.

  JUSTICE KAVANAUGH took no part in the consideration
or decision of this case.
                 Cite as: 586 U. S. ____ (2019)            1

                    GINSBURG, J., concurring

SUPREME COURT OF THE UNITED STATES
                          _________________

                          No. 17–340
                          _________________


           NEW PRIME INC., PETITIONER v.
                DOMINIC OLIVEIRA
 ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF
             APPEALS FOR THE FIRST CIRCUIT
                      [January 15, 2019]

  JUSTICE GINSBURG, concurring.
  “[W]ords generally should be ‘interpreted as taking their
ordinary . . . meaning . . . at the time Congress enacted the
statute.’ ” Ante, at 6 (quoting Wisconsin Central Ltd. v.
United States, 585 U. S. ___, ___ (2018) (slip op., at 9)).
The Court so reaffirms, and I agree. Looking to the period
of enactment to gauge statutory meaning ordinarily fos-
ters fidelity to the “regime . . . Congress established.” MCI
Telecommunications Corp. v. American Telephone & Tele-
graph Co., 512 U. S. 218, 234 (1994).
  Congress, however, may design legislation to govern
changing times and circumstances. See, e.g., Kimble v.
Marvel Entertainment, LLC, 576 U. S. ___, ___ (2015) (slip
op., at 14) (“Congress . . . intended [the Sherman Antitrust
Act’s] reference to ‘restraint of trade’ to have ‘changing
content,’ and authorized courts to oversee the term’s ‘dy-
namic potential.’ ” (quoting Business Electronics Corp. v.
Sharp Electronics Corp., 485 U. S. 717, 731‒732 (1988)));
SEC v. Zandford, 535 U. S. 813, 819 (2002) (In enacting
the Securities Exchange Act, “Congress sought to substi-
tute a philosophy of full disclosure for the philosophy of
caveat emptor . . . . Consequently, . . . the statute should
be construed not technically and restrictively, but flexibly
to effectuate its remedial purposes.” (internal quotation
marks and paragraph break omitted)); H. J. Inc. v.
2               NEW PRIME INC. v. OLIVEIRA

                    GINSBURG, J., concurring

Northwestern Bell Telephone Co., 492 U. S. 229, 243 (1989)
(“The limits of the relationship and continuity concepts
that combine to define a [Racketeer Influenced and Cor-
rupt Organizations] pattern . . . cannot be fixed in advance
with such clarity that it will always be apparent whether
in a particular case a ‘pattern of racketeering activity’
exists. The development of these concepts must await
future cases . . . .”). As these illustrations suggest, some-
times, “[w]ords in statutes can enlarge or contract their
scope as other changes, in law or in the world, require
their application to new instances or make old applica-
tions anachronistic.” West v. Gibson, 527 U. S. 212, 218
(1999).
