          United States Court of Appeals
                      For the First Circuit


Nos. 16-1370
     16-1406
                   WAL-MART PUERTO RICO, INC.,

                       Plaintiff, Appellee,

                                v.

       JUAN C. ZARAGOZA-GOMEZ, in his official capacity as
  Secretary of the Treasury of the Commonwealth of Puerto Rico,

                      Defendant, Appellant.


          APPEAL FROM THE UNITED STATES DISTRICT COURT
                FOR THE DISTRICT OF PUERTO RICO

         [Hon. José Antonio Fusté, U.S. District Judge]


                              Before

                  Lynch, Thompson, and Kayatta,
                         Circuit Judges.


     Margarita L. Mercado-Echegaray, Solicitor General, Department
of Justice, Commonwealth of Puerto Rico, and Susan Seabrook, with
whom H. Marc Tepper, Buchanan Ingersoll & Rooney PC, and Susana
Peñagaricano-Brown, Assistant Solicitor General, Department of
Justice, Commonwealth of Puerto Rico, were on brief, for appellant.
     Joseph S. Grinstein, with whom Neal S. Manne, Shawn Rabin,
Steven M. Shepard, Susman Godfrey LLP, Juan A. Marqués-Díaz,
Francisco G. Bruno, Alejandro J. Cepeda-Diaz, and McConnell Valdés
LLC were on brief, for appellee.


                         August 24, 2016
          LYNCH, Circuit Judge.     Wal-Mart Puerto Rico, Inc. ("Wal-

Mart PR") brought this suit against the Puerto Rico Secretary of

the Treasury to challenge the lawfulness of Puerto Rico's corporate

alternative minimum tax ("AMT"), as amended in May 2015.             The

district court held that it had jurisdiction over the suit and

enjoined the enforcement of the AMT after concluding that the AMT

violates the dormant Commerce Clause; the Federal Relations Act,

48 U.S.C. § 741a; and the Equal Protection Clause.        Wal-Mart P.R.,

Inc. v. Zaragoza-Gómez, No. 3:15-CV-03018, 2016 WL 1183091, at *51

(D.P.R. Mar. 28, 2016).

          We   affirm,    which   continues   the   injunction   against

enforcement of the AMT against Wal-Mart PR.         The federal district

court did have jurisdiction because Wal-Mart PR, at the time of

suit, lacked a plain, speedy, and efficient remedy in the Puerto

Rico courts due to changes in legislation and regulation.             As

applied to these facts, those changes imposed a maximum recovery

limit of $3 million per year against a potential tax reimbursement

judgment by the Puerto Rico courts of over $200 million total ($30

to $40 million a year) and an estimated 4.6 years to judgment.

Even that annual $3 million would not have been guaranteed to be

paid, especially in light of mandated priorities putting other

debts ahead of taxpayer debt.      As to the merits of the Commerce

Clause challenge, the AMT is a facially discriminatory statute




                                  - 2 -
that does not meet the heightened level of scrutiny required to

survive under the dormant Commerce Clause.

                              I. Facts

           The Commonwealth of Puerto Rico is in dire financial

straits.    Puerto Rico v. Franklin Cal. Tax-Free Tr., 136 S. Ct.

1938, 1942 (2016); Puerto Rico Oversight, Management, and Economic

Stability Act ("PROMESA"), Pub. L. No. 114-187, 130 Stat. 549

(2016).    As the district court summarized its findings:

           [T]he Commonwealth is being crushed under the
           weight of a public debt that is larger than
           its gross national product, Puerto Rico's
           annual budget is running a structural deficit
           that   is   about  [to]   explode   into   the
           multibillion-dollar range, the government's
           cash reserves are about to dry out, its credit
           rating is at junk status, it has started to
           default on its debt obligations, and it has no
           place to turn for external funding, including
           the possibly-insolvent Government Development
           Bank.

Wal-Mart P.R., Inc., 2016 WL 1183091, at *8.1

A.   The Amended AMT

           Against this backdrop, the Puerto Rico legislature, in

an effort to raise more tax revenue, amended the AMT in May 2015,

as part of Act 72 of 2015.     We begin by discussing the general




     1    We take judicial notice of the fact that since the
district court judgment, the sum of Puerto Rico's official debt
has only increased. On July 1, 2016, the Commonwealth defaulted
on over $800 million in debt payments.


                                - 3 -
structure of the AMT in order to explain the two ways in which Act

72 amended the AMT.

          The AMT is a tax equal to the amount (if any) by which

a corporate taxpayer's tentative minimum tax exceeds its regular

tax on income.    P.R. Laws Ann. tit. 13, § 30073(a).2   The tentative

minimum tax is defined as the higher of two measures.              Id.

§ 30073(b).      The first measure, which is not relevant here, is

calculated    from     the   corporate   taxpayer's   income.      Id.

§ 30073(b)(1).       The second measure, which is at issue here, is

calculated from the value of goods and services sold or otherwise

provided to the corporate taxpayer by a related entity or home

office located outside of Puerto Rico.      Id. § 30073(b)(2).

          This second measure is the sum of two components: an

expenses tax and a tangible-property tax.      Id.    The expenses tax

is a 20% tax on services provided to the corporate taxpayer by a




     2    The most recent official English translation of the AMT
statute predates the 2015 amendment at issue in this case.      We
rely instead on a certified English translation of the statute
that the parties provided to the district court and reproduced in
the addendum to the Secretary's brief on appeal. The parties agree
that the translation is complete, accurate, and up-to-date.



                                 - 4 -
related party3 or     home office4 outside      of Puerto Rico.           Id.

§ 30073(b)(2)(A).    The tangible-property tax is a tax on the goods

sold or transferred to the corporate taxpayer by a related party

or home office outside of Puerto Rico.              Id. § 30073(b)(2)(B).

Prior to the 2015 amendment, the tangible-property tax was a 2%

flat tax.   The 2015 amendment provided new graduated rates for the

AMT's tangible-property tax, with a top rate of 6.5% for corporate

taxpayers with $2.75 billion or more in gross sales in Puerto Rico.

            The   Secretary   acknowledged   that    the   purpose   of   the

expenses and tangible-property taxes is to prevent multistate

corporations doing business in Puerto Rico from shifting profits

off the island by purchasing goods and services from related

mainland entities at artificially inflated prices.          The concern is

that by manipulating prices for such transactions between related

entities, a multistate taxpayer can shift profits to another

jurisdiction with a lower tax rate and thereby artificially deflate

its Puerto Rico income tax burden.        The AMT accordingly applies



     3    An entity and a corporate taxpayer are "related parties"
when they are both members of the same controlled group of
corporations; one of them owns, directly or indirectly, 50% or
more of the other's stock; or a single person owns, directly or
indirectly, 50% or more of each of their stocks. P.R. Laws Ann.
tit. 13, § 30045(b).

     4    Puerto Rico law does not define "home office," but it
appears to mean the headquarters of a "branch engaged in trade or
business   in  Puerto   Rico."     P.R.   Laws   Ann.  tit.   13,
§ 30073(b)(2)(B).


                                  - 5 -
only to transactions between a Puerto Rico taxpayer and a related

entity located outside of Puerto Rico.

            The absence of a potential problem of profit-shifting

from a Puerto Rico taxpayer to a related entity outside of Puerto

Rico may be indicated by a transfer price that is the same as the

price at which unrelated parties would arrive through arm's-length

negotiation. As such, prior to the 2015 amendment, the AMT statute

provided that the Secretary could tax a related-party transaction

at a lower rate if he found that the transfer price paid by the

taxpayer to the related entity was "equal or substantially similar

to the [price] for which such related party sells such property to

an unrelated party."       Id. § 30073(d)(4).   In addition to the new

graduated    rates   for    the   tangible-property   tax,   the   second

significant change in the 2015 AMT amendment was the elimination

of this exemption.

            The Secretary conceded in testimony before the district

court that the amended AMT is no longer targeted at profit-shifting

through transfer-pricing abuse but is instead simply "a revenue

raising measure."    The district court credited this testimony and

found that the amendment to the AMT was intended to raise tax

revenues from multistate mega-retailers like Wal-Mart PR.           Wal-

Mart PR further alleges, and Puerto Rico does not dispute, that it

is the only corporation that meets the sales threshold for the top

tangible-property tax rate of 6.5%. Indeed, the new top rate under


                                   - 6 -
the amended AMT is alleged to be essentially a "Wal-Mart tax,"

passed to raise a specific level of revenue from Wal-Mart PR in

light of Puerto Rico's budget crisis.

B.    Wal-Mart PR

            Wal-Mart PR is the largest private employer in Puerto

Rico.     It operates forty-eight stores in Puerto Rico and employs

around 14,300 people.         Each year, it buys around $1.6 billion of

inventory locally and over $700 million of inventory from its

parent    company,   Wal-Mart     Stores,   Inc.,   and    related   mainland

entities. Each year, Wal-Mart PR earns roughly $3 billion in sales

in Puerto Rico.

            Wal-Mart PR's tax year begins on February 1.              The tax

year commencing February 1, 2015 and ending January 31, 2016 (which

we will call Fiscal Year 20165) was the first year in which Wal-

Mart PR was subject to the new graduated tangible-property tax

rate in the amended AMT.

            In Fiscal Year 2012, Wal-Mart PR's total income tax

liability to Puerto Rico was $19.9 million.            The following year,

it was $18.6 million.    But in Fiscal Year 2016, Wal-Mart PR's total

tax   liability   rose   to    approximately   $46.5      million,   of   which

approximately $32.9 million would have been attributable to the



      5   "Fiscal Year 2016" actually consists of eleven months
that were in calendar year 2015.     Nonetheless, we adopt this
nomenclature because it is what Wal-Mart PR chooses to use.


                                    - 7 -
amended AMT had the district court not enjoined that tax.6   Wal-

Mart PR alleges that the amended AMT, if enforced, would have made

its total tax liability 132% of the company's total annual income.

The AMT makes this percentage possible because the AMT taxes the

transfer of goods and services to the corporate taxpayer, and it

is not keyed to the taxpayer's income. For a retailer like Wal-

Mart PR that engages in a high volume of transactions with low

profit margins on each item sold, this feature of the AMT can

result in a particularly high tax liability relative to income.

          Wal-Mart PR estimates that in future years, it will pay

$40 million per year as a result of the amended AMT and that its

annual effective tax rate will be over 300%.

                     II. Procedural History

          On December 4, 2015, Wal-Mart PR commenced this action

against Puerto Rico Secretary of the Treasury Juan Zaragoza-Gómez

in his official capacity.   Wal-Mart PR sought, under 42 U.S.C.

§ 1983, an injunction against the continued enforcement of the AMT

against it and a declaration that the AMT is unlawful under the




     6    On August 15, 2016, Wal-Mart PR submitted a Rule 28(j)
letter notifying the court that it had filed its tax return for
Fiscal Year 2016.   Before this date, Wal-Mart PR had estimated
that its tax liability for Fiscal Year 2016 would be $47 million,
with $30.9 million of that sum attributable to the AMT. We note
that Puerto Rico objects to our use of the information that Wal-
Mart PR provided in its 28(j) letter and that Puerto Rico has not
yet audited Wal-Mart PR's tax return for Fiscal Year 2016.


                              - 8 -
dormant Commerce Clause; the Equal Protection Clause; the Bill of

Attainder Clauses; and the Federal Relations Act, 48 U.S.C. § 741a.

           On December 21, 2015, the Secretary filed a Rule 12(b)(1)

motion to dismiss for lack of subject matter jurisdiction.              The

district court deferred resolution of the motion, citing the need

for jurisdictional discovery.        Following an expedited discovery

period,   the   district   court   held    an   evidentiary   hearing   from

February 2 to 5, 2016.

           On March 28, 2016, the district court issued an order

stating its findings of fact and conclusions of law.          Fed. R. Civ.

P. 52(a)(1). The district court held that: (1) it had jurisdiction

under the Butler Act because of the lack of a "plain, speedy and

efficient remedy" in Puerto Rico courts; (2) the AMT violates the

dormant Commerce Clause; (3) the AMT violates the Federal Relations

Act; (4) the AMT violates the Equal Protection Clause; and (5) the

AMT does not violate the Bill of Attainder Clauses.             As for the

relief entered, the court "permanently enjoin[ed] and declare[d]

invalid, under both federal constitutional and statutory law,

section 1022.03(b)(2) and (d) of the Puerto Rico Internal Revenue

Code of 2011."    Wal-Mart P.R., Inc., 2016 WL 1183091, at *51.         The

court ordered the injunction to go into effect immediately.

           This appeal followed.




                                   - 9 -
                              III. Jurisdiction

             Before we reach the constitutionality of the amended

AMT,    we   must   address   three    threshold   matters    raised   by    the

Secretary: whether lack of standing or ripeness bars this suit,

whether the Butler Act bars the exercise of federal district court

jurisdiction in this case, and whether the principle of comity

requires dismissal of this case.          We take each in turn.

A.     Standing and Ripeness

             The Secretary argues that Wal-Mart PR had no standing to

bring this suit because it had not filed a tax return prior to

filing its complaint.         The Secretary makes essentially the same

argument in ripeness terms, arguing that the district court erred

by treating Wal-Mart PR's payment of estimated quarterly taxes as

sufficient to meet justiciability requirements.              Our review is de

novo.    Summers v. Fin. Freedom Acquisition LLC, 807 F.3d 351, 355

(1st Cir. 2015); Sullivan v. City of Augusta, 511 F.3d 16, 24 (1st

Cir. 2007).

             Even though Wal-Mart PR had not filed its tax return at

the commencement of this suit in the district court, it had already

begun paying estimated quarterly taxes under the amended AMT

statute prior to filing suit.          Those estimated quarterly payments

were required by law, and nonpayment was subject to penalty.                P.R.

Laws Ann. tit. 13, § 30263(a), (h).            Moreover, Puerto Rico law

provides that "[p]ayment of the estimated tax . . . shall be


                                      - 10 -
treated as payment on account of the tax for the taxable year."

Id. § 30263(g).      Wal-Mart PR suffered a sufficiently cognizable

injury in fact by the legally compelled payment of estimated taxes.

And the fact that, at the time of adjudication before the district

court, the exact tax figure was subject to adjustment upon the

filing of the tax return did not prevent this case from being ripe

for adjudication.     The Secretary never contested that Wal-Mart PR

was subject to some level of tax liability under the challenged

version   of   the   AMT,   and   no   further   factual   development   was

necessary.     See Verizon New Eng., Inc. v. Int'l Bhd. of Elec.

Workers, Local No. 2322, 651 F.3d 176, 188 (1st Cir. 2011).7

Accordingly, we hold that Wal-Mart PR had standing to bring this

suit and that the case was sufficiently ripe.

B.   The Butler Act's Jurisdictional Bar

           1.   Does the Butler Act contain an exception to its
           jurisdictional bar?

           The Secretary argues that even if standing and ripeness

requirements are met, the Butler Act's jurisdictional bar deprives

the Puerto Rico federal district court of jurisdiction over this


     7    At oral argument, we asked the Secretary to provide us
with citations to what the Secretary claimed was a line of Supreme
Court cases holding that estimated tax payments do not suffice to
confer Article III standing to challenge a tax. See Fed. R. App.
P. 28(j).    The case citations that the Secretary submitted,
however, related to federal statutory prerequisites to filing a
federal tax-refund suit and were entirely irrelevant to the
question of Article III justiciability. We have conducted our own
search and found no such cases either.


                                   - 11 -
action.   Wal-Mart PR, as the party invoking federal jurisdiction,

has the burden of proving its existence.             Calderón-Serra v.

Wilmington Tr. Co., 715 F.3d 14, 17 (1st Cir. 2013).           We review

the district court's findings on jurisdictional facts for clear

error, but review its ultimate legal conclusion on jurisdiction de

novo.   See United States ex rel. Ondis v. City of Woonsocket, 587

F.3d 49, 54 (1st Cir. 2009); Valentin v. Hosp. Bella Vista, 254

F.3d 358, 365-66 (1st Cir. 2001).          Puerto Rico does not contest

the factual findings made, but contests the conclusions drawn from

those facts.

          The Butler Act states: "No suit for the purpose of

restraining the assessment or collection of any tax imposed by the

laws of Puerto Rico shall be maintained in the United States

District Court for the District of Puerto Rico."         48 U.S.C. § 872.

The parties agree that this jurisdictional bar contains an unstated

exception: it presumes that the Commonwealth itself provides a

"plain, speedy and efficient" remedy for a taxpayer harmed by the

imposition    of   an   unconstitutional    tax.   Our   own   court   has

repeatedly acknowledged the likely existence of such an exception,

but we have never found it applicable.         See, e.g., Coors Brewing

Co. v. Méndez-Torres, 562 F.3d 3, 13 & n.5 (1st Cir. 2009),

abrogated on other grounds by Levin v. Commerce Energy, Inc., 560

U.S. 413 (2010); Carrier Corp. v. Perez, 677 F.2d 162, 164 (1st

Cir. 1982).    Nor have we explained in any detail why the exception


                                 - 12 -
does exist.   Because we ultimately find the exception applicable

in this case and because the existence of jurisdiction is a matter

that we must raise and ascertain sua sponte, see McCulloch v.

Vélez, 364 F.3d 1, 5 (1st Cir. 2004), we begin by explaining why

we agree with the parties that this appeal turns on whether the

exception applies, not on whether it exists.

          Long before the enactment of the Butler Act, federal

courts of equity refused to interfere with the collection of state

taxes.   See, e.g., Great Lakes Dredge & Dock Co. v. Huffman, 319

U.S. 293, 299 (1943).   Nonetheless, the common law recognized an

exception for those cases in which "the threatened injury to the

taxpayer [wa]s one for which the state courts afford[ed] no

adequate remedy."   Id.; see also Union Pac. R.R. Co. v. Bd. of

Cty. Comm'rs, 247 U.S. 282, 285 (1918) (collecting cases for the

proposition that if state revenue laws provided a "plain, adequate

and complete remedy at law" to refund tax payments, "relief by

injunction [wa]s not admissible").8




     8    In fact, while interpreting a similar, seemingly
absolute statutory provision, which is currently codified at 26
U.S.C. § 7421 and states that "no suit for the purpose of
restraining the assessment or collection of any tax shall be
maintained in any court," the Supreme Court emphasized that
"never," since that statute's enactment in 1867, had it "held the
rule to be absolute, but ha[d] repeatedly indicated that
extraordinary and exceptional circumstances render its provisions
inapplicable." Miller v. Standard Nut Margarine Co. of Fla., 284
U.S. 498, 509–10 (1932) (collecting cases dating back to 1916);
see also Allen v. Regents, 304 U.S. 439, 449 (1938) ("The statute


                              - 13 -
            Against this backdrop, Congress enacted the Butler Act

of 1927.     In light of the longstanding common-law recognition of

an exception to the general jurisdictional bar, the Butler Act is

presumed to include that exception.           See Norfolk Redev. & Hous.

Auth. v. Chesapeake & Potomac Tel. Co. of Va., 464 U.S. 30, 35–36

(1983)     ("It   is   a   well-established     principle   of   statutory

construction that '[t]he common law . . . ought not to be deemed

to be repealed, unless the language of a statute be clear and

explicit for this purpose.'" (alterations in original) (quoting

Fairfax's Devisee v. Hunter's Lessee, 11 U.S. (7 Cranch) 603, 623

(1813))); see also U.S. Brewers Ass'n, Inc. v. Perez, 592 F.2d

1212, 1213 n.2 (1st Cir. 1979) ("The district court's reluctance

to read the Butler Act as an absolute ban, construing it instead

'in a manner consistent with general equitable principles' was

generally in accord with the limited case law applying that Act."),

abrogated on other grounds by Coors Brewing Co., 562 F.3d 3.

            The legislative history of the Butler Act only confirms

this reading.     The principal purpose of the statute was to "apply

the same rule [of tax collection and litigation] in P[ue]rto Rico

that now applies on the continent of the United States."            Sancho

v. Nat'l City Bank of N.Y., 112 F.2d 998, 999 (1st Cir. 1940)

(quoting 68 Cong. Rec. S5025 (daily ed. Feb. 28, 1927) (statement


is inapplicable in exceptional cases where there is no plain,
adequate, and complete remedy at law.").


                                  - 14 -
of Sen. Bingham)).       To the extent that the pre-Butler Act common

law in the continental United States recognized an exception to

the federal jurisdictional bar and that the Butler Act's purpose

was to "make the condition [in Puerto Rico] just the same as in

the United States," 68 Cong. Rec. S5026 (daily ed. Feb. 28, 1927)

(statement of Sen. Bingham), reading the Butler Act to include the

exception as well is consistent with the drafters' purpose.                    By

including the exception, we also avoid construing the statute in

a manner that suggests Congress would set up a jurisdictional

system in which an aggrieved taxpayer would have no recourse,

either local or federal.

           The enactment of the Tax Injunction Act of 1937 ("TIA"),

28 U.S.C. § 1341, further evinces Congress's adherence to the

tradition of preserving an exception to the federal jurisdictional

bar where taxpayers had no remedy in state courts after paying an

illegal   tax.     The    TIA   deprives       federal    district    courts   of

jurisdiction to enjoin the collection of state taxes.                  Pleasures

of San Patricio, Inc. v. Méndez-Torres, 596 F.3d 1, 5 (1st Cir.

2010); see also Hibbs v. Winn, 542 U.S. 88, 109 n.11 (2004).

Congress intended the TIA to be "first and foremost a vehicle to

limit drastically federal district court jurisdiction to interfere

with so important a local concern as the collection of taxes."

Rosewell v. LaSalle Nat'l Bank, 450 U.S. 503, 522 (1981).                 After

all,   states    rely    on   taxes     "to    carry     on   their   respective


                                      - 15 -
governments," and "[a]ny delay in the proceedings of the officers,

upon whom the duty is devolved of collecting the taxes, may derange

the operations of government, and thereby cause serious detriment

to the public."      Fair Assessment in Real Estate Ass'n, Inc. v.

McNary, 454 U.S. 100, 127 (1981) (Brennan, J., concurring in the

judgment) (quoting Dows v. City of Chicago, 78 U.S. (11 Wall.)

108, 110 (1871)).

            But, unlike the Butler Act, the TIA contains an express

exception    under   which    federal   district   courts   can   assume

jurisdiction where state courts do not provide a "plain, speedy

and efficient remedy."       28 U.S.C. § 1341.   The historical context

in which each statute was enacted helps explain why Congress

expressly codified an exception in the TIA when it did not do so

in the Butler Act.    The Senate floor statements of the Butler Act's

drafters imply that Puerto Rico, at the time of enactment, provided

a remedy for illegal tax payments.      See 68 Cong. Rec. S5026 (daily

ed. Feb. 28, 1927) (Sen. Norris: "There is ample provision made,

as I understand the law, for the return of taxes that are illegally

paid." Sen. Bingham: "Oh, yes; there is no question about that.").

Not all states at that time, however, provided such recourse for

taxes paid under protest.      See Grosjean v. Am. Press Co., 297 U.S.

233, 242 (1936).     As Puerto Rico offered a remedy that some states

did not, articulating the implied equitable exception in the text

of the Butler Act may not have seemed critical to its drafters.


                                  - 16 -
              By contrast, when Congress enacted the TIA ten years

later, the need to affirmatively build the exception into the

statutory text was more pronounced.                First, as discussed above,

some states at the time "afford[ed] no remedy whereby restitution

of taxes and property exacted m[ight] be enforced, even where

payment ha[d] been made under both protest and compulsion."                    Id.

Furthermore,        the   Great   Depression     had   intervened    between   the

passage of the Butler Act in 1927 and the TIA in 1937, resulting

in scenarios in which even those states that had in place remedial

schemes could not provide relief in fact.                 See, e.g., Stewart Dry

Goods   Co.    v.    Lewis,    287   U.S.   9,    10-11    (1932)   (per   curiam)

(recognizing that despite formal remedy available under Kentucky

law, taxpayers could not actually collect, "for lack of funds in

the Treasury").           In light of the disparate laws and financial

realities of the various states at the time of the TIA's enactment,

it makes sense that the TIA expressly codifies the exception

included impliedly in the Butler Act.

              Of course, although the TIA has its roots in federal

equity practice, its exception is statutory and not equitable.                  In

Rosewell, the Court cautioned that the TIA's "plain, speedy and

efficient remedy" exception should not necessarily be read as

"coterminous with pre-1937 federal equity treatment of challenges

to state taxes."          450 U.S. at 524.       Rosewell serves two purposes.

It first recognizes the "longstanding rule of federal equity to


                                      - 17 -
keep out of state tax matters as long as a 'plain, adequate and

complete remedy' could be had at law."     Id. at 525.   Second, by

construing the TIA's exception as narrower than prior federal

equity practice, Rosewell signals that the role of the federal

courts is now to interpret the precise language of the statutory

exception, rather than rely on the former, more amorphous equitable

exception standard.

           As acknowledged above, the Butler Act and the TIA "have

been construed in pari materia" in our circuit, which has extended

the TIA's exception to the Butler Act.9   Pleasures of San Patricio,

596 F.3d at 5 (quoting United Parcel Serv., Inc. v. Flores-Galarza,

318 F.3d 323, 330 n.11 (1st Cir. 2003)).    Accordingly, the Butler

Act has been interpreted to allow the Puerto Rico federal district

court to enjoin a Puerto Rico tax where there was no plain, speedy

and efficient remedy, presumably within the meaning of the TIA,

available in the Puerto Rico courts.        Id.    This "judicially

engrafted exception" to the Butler Act is well established in this

circuit.   Parker v. Agosto-Alicea, 878 F.2d 557, 558–59 (1st Cir.

1989); Carrier Corp., 677 F.2d at 164.




     9    Reading the Butler Act to include the TIA's exception is
indeed consistent with the canon of in pari materia. The Supreme
Court has invoked that canon of statutory construction to use the
meaning of a later statute in helping interpret an earlier statute
of similar subject matter.    See, e.g., Fanning v. Gregoire, 57
U.S. (16 How.) 524, 529 (1854).


                              - 18 -
          At the conclusion of our survey of the Butler Act and

the TIA, we must acknowledge that the timeline of the two statutes'

enactments suggests that the Butler Act of 1927 incorporated the

common law equitable exception, but we cannot say whether our

subsequent construction of the Butler Act in pari materia with the

TIA narrowed that exception.    We need not resolve this question

here, however, as this case qualifies under the narrower TIA

exception, and that is all that Wal-Mart PR itself claims.    After

independently reviewing the historical context and legislative

history of the Butler Act and TIA, we reaffirm that the Butler

Act's jurisdictional bar is subject to an exception that is at

least coextensive with the TIA's exception.

          2.   Is this case within the exception to the Butler Act?

          The parties agree that this suit has the purpose of

restraining the assessment or collection of a Puerto Rico tax, so

the jurisdictional bar of the Butler Act is in play.   The remaining

question is whether the exception to the Butler Act applies on the

basis that, under Puerto Rico law, the Puerto Rico courts cannot

provide a plain, speedy, and efficient remedy.   If that exception

does not apply, then the Butler Act bars the district court from

exercising jurisdiction, and we would dismiss the case without

reaching the question of the amended AMT's constitutionality.     By

far this is the most difficult question presented by this case.




                               - 19 -
               The only local remedy available to Wal-Mart PR in the

Puerto Rico courts is Puerto Rico's tax-refund process.               P.R. Laws

Ann. tit. 13, § 261; Pleasures of San Patricio, Inc., 596 F.3d at

7.   Under the tax-refund process, a taxpayer contesting a tax must

first pay the contested tax and then file a tax return requesting

a refund or credit from the Secretary of the Treasury.                Pleasures

of San Patricio, Inc., 596 F.3d at 7.            If the Secretary denies the

refund, the taxpayer may appeal the denial in the Puerto Rico court

system and then seek review by certiorari in the United States

Supreme Court.       Id. at 8.   We have held in previous cases -- before

enactment of the amended AMT now being challenged, the Special

Fiscal       and   Operational   Sustainability     Act   of   2014   ("Fiscal

Sustainability Act"), and Treasury regulations awarding priority

to other Puerto Rico debt payments over tax refunds -- that this

tax-refund process is a plain, speedy, and efficient remedy for

the purpose of the Butler Act because it provides the taxpayer

with     a    full    hearing    and     judicial   determination      of   any

constitutional objections to a tax.              Id. at 8–9; Carrier Corp.,

677 F.2d at 164.

               The   district    court    held   that   notwithstanding     our

previous cases, Puerto Rico's current financial legislation and

status compelled the opposite conclusion.                 The district court

projected that under the most conservative estimate, in which

denial of the refund by the Treasury takes one year and Wal-Mart


                                       - 20 -
PR successfully obtains an injunction on the collection of the AMT

from the Puerto Rico Court of First Instance, Wal-Mart PR would be

entitled to a $70 million tax refund -- the $30 million for Fiscal

Year 2016 and another estimated $40 million for the following year.

Wal-Mart PR asserts that the more realistic tax-refund liability

figure if it continues to do business in Puerto Rico at the present

AMT rate is $214 million.10       The district court found that Puerto

Rico would be unable under the current state of affairs to satisfy

a judgment of $70 million (or, for that matter, $214 million).

              More critically, the district court noted that Puerto

Rico    law   had   recently   been    altered,   as   part   of   the   Fiscal

Sustainability Act, to impose a new obstacle by capping the payment

of any judgment exceeding $20 million against the Commonwealth at

$3 million per year.       The district court also noted that Puerto

Rico can refuse to honor even that $3 million annual payment

"whenever it finds there are 'no funds available' that year." Wal-

Mart P.R., Inc., 2016 WL 1183091, at *30.              It further found that

such postponement is likely to occur almost indefinitely because


       10 Wal-Mart PR's estimate is based on the assumption that
the Puerto Rico Court of First Instance will not have the power to
enjoin the AMT and that Wal-Mart PR would have to continue paying
the AMT until the Puerto Rico Supreme Court decides the matter.
Wal-Mart P.R., Inc., 2016 WL 1183091, at *27.      The figure was
calculated by multiplying 4.6 years, which the district court
estimated as the "average" litigation time until a Puerto Rico
Supreme Court decision, by $40 million in AMT payments per year
and then adding that to the $30 million for Fiscal Year 2016. Id.
at *28.


                                      - 21 -
recent Puerto Rico Treasury guidelines prioritize payment of other

government obligations over the payment of tax refunds.         In

addition, the district court concluded that there were no tax

credits available under Puerto Rico law that would suffice as an

alternative adequate remedy for Wal-Mart PR.   The district court's

reasoning, in short, was that even if Puerto Rico law furnishes

Wal-Mart PR with a sufficient procedural avenue for challenging

the AMT, there is still no plain, speedy, and efficient remedy

because of the inability of Puerto Rico courts to see to it that

an ultimate judgment in favor of Wal-Mart PR is satisfied.      In

response, Puerto Rico asserts that it may force Wal-Mart PR to pay

over $200 million in unconstitutionally imposed taxes and make

Wal-Mart PR wait a minimum of seventy years for repayment, if then.

          We agree with the district court that Puerto Rico has

now hamstrung its courts so as to deprive Wal-Mart PR of a plain,

speedy, and efficient remedy at the time of this suit.     Indeed,

the local remedy available to Wal-Mart PR today is fundamentally

different from what would have been available before the enactment

of the Fiscal Sustainability Act and recent Treasury guidelines.

To elaborate, the Secretary does not challenge the district court's

projection that, even under the most conservative estimate, the

Puerto Rico tax-refund process would require Wal-Mart PR to make

$70 million in AMT payments before Wal-Mart PR can, if then, obtain

an injunction against the AMT in the Puerto Rico courts.   Nor does


                              - 22 -
the Secretary challenge the district court's prediction that,

because of the $3 million statutory cap, Wal-Mart PR may never

receive a full refund.        And even if it does, the full refund will

take well over the apparent minimum of two decades because payment

of even $3 million per year is likely to be postponed indefinitely,

with no evident recourse for Wal-Mart PR.

            The Secretary instead argues that even a total inability

by Puerto Rico to satisfy a tax-refund judgment would not justify

federal jurisdiction because "plain, speedy, and efficient" refers

only to the procedural adequacy of Puerto Rico's local remedy.

According   to    the   Secretary,     Puerto   Rico's   tax-refund    process

provides    the    taxpayer     with    a     full   hearing   and    judicial

determination of any constitutional objections to the tax, and

Wal-Mart PR's ability to obtain a tax-refund judgment through that

procedure makes the Puerto Rico remedy a plain, speedy, and

efficient one.      Under that reasoning, we would make no inquiry

into what happens after the Puerto Rico judicial process produces

a tax-refund judgment.      Of course, that would require us to ignore

the word "remedy" in the Act.

            The Secretary's argument relies on the Supreme Court's

decision in Rosewell.       In our view, the Secretary overreads that

case.   In Rosewell, the Court held that Illinois's tax-refund

procedure was a plain, speedy, and efficient remedy for a tax

challenger even though a successful challenger would wait two years


                                     - 23 -
and receive no interest for any taxes refunded.   450 U.S. at 528.

In so holding, the Supreme Court used language suggesting that

"plain, speedy and efficient" in the TIA refers to the "procedural"

adequacy of the local remedy, id. at 512, rather than the "more

substantive concern" of whether the recovery included payment of

interest, id. at 515.

          But unlike in this case, there is no indication in

Rosewell that the county government was unable to pay the full

value (without interest) of the tax refund at the conclusion of

the refund process in the courts.   See, e.g., id. at 507 n.5.   We

do not read Rosewell as bearing on a situation where, as alleged

here, the taxpayer is afforded adequate process in obtaining a

tax-refund judgment but where local laws also largely insure that

the judgment is worthless for all practical purposes.   Indeed, in

light of the annual $3 million cap on payments of judgments against

the Commonwealth and the discretion it has to reduce even that

amount, the priority given other debts over Wal-Mart PR's debt,

and the notably large sum (far exceeding the $3 million cap for

every year of tax liability) that Wal-Mart PR would be owed by the

time a Puerto Rico court ruled on the matter and Wal-Mart PR

prevailed,11 Wal-Mart PR's AMT payments, if unconstitutional, would


     11   We note that the Puerto Rico Supreme Court has not
recognized the full applicability of the dormant Commerce Clause
to Puerto Rico.   See, e.g., Starlight Sugar, Inc. v. Soto, 253
F.3d 137, 142–43 (1st Cir. 2001) (noting Puerto Rico Supreme


                              - 24 -
effectively be uncollectable.          This would be so even after Wal-

Mart PR completed the tax-refund process and obtained a successful

judgment.    Given these realities, in our view, Puerto Rico law

does not provide a plain, speedy, and efficient remedy to bar

federal district court jurisdiction over this case.

            Two Supreme Court cases and at least one circuit case

support our conclusion that a local government's inability to

satisfy a tax-refund judgment, thus depriving a taxpayer of any

"remedy," could make a local tax-refund process inadequate so as

to support federal injunctive relief.        In Matthews v. Rodgers, the

Supreme Court stated that a local tax-refund action is an "adequate

legal   remedy"   that   forecloses     exercise   of   federal   equitable

jurisdiction    unless   there   are    "special   circumstances   showing

inability of . . . the collecting officer to respond to the

judgment."     284 U.S. 521, 528 (1932).

            Also, in Stewart Dry Goods, the Supreme Court vacated

the district court's dismissal of a tax challenge and remanded it

to the district court for further factfinding on whether the local


Court's comment: "This interstate commerce relation [between
Puerto Rico and the United States] has constitutionally had, and
still has, contours which are different from the relation which
under the Constitution prevails among states of the Union."
(alteration in original) (quoting R.C.A. v. Gov't of the Capital,
91 P.R.R. 404, 419 (P.R. 1964))). If Wal-Mart PR were to litigate
this matter in the Puerto Rico system and the Puerto Rico Supreme
Court refused to find that the transfer-based AMT violated the
Commerce Clause, Wal-Mart PR's only remaining recourse would be
potential review of that decision by the U.S. Supreme Court.


                                  - 25 -
tax-refund procedure was inadequate because, at the time of the

suit's    commencement,   there   were     already   outstanding   unpaid

warrants totaling $9.8 million against Kentucky's general fund

that "c[ould] not be collected . . . for lack of funds in the

Treasury."     287 U.S. at 11.     The district court on remand took

jurisdiction    upon   finding    Kentucky's    tax-refund    procedures

inadequate, Stewart Dry Goods Co. v. Lewis, 7 F. Supp. 438, 440

(W.D. Ky. 1933), and the Supreme Court accepted jurisdiction

without question in a subsequent appeal on the merits question of

the state tax's constitutionality, Stewart Dry Goods Co. v. Lewis,

294 U.S. 550, 552 (1935).12

           Finally, in Adams County v. Northern Pacific Railway

Co., the Ninth Circuit cited Stewart Dry Goods in holding that a

local tax-refund procedure was not plain, speedy, and efficient

for the purpose of the TIA where "some of the defendant counties

[we]re insolvent and . . . in consequence a judgment for plaintiff

in such an action would, as to such counties, result only in the

issuance of uncollectible warrants."        115 F.2d 768, 776 (9th Cir.

1940).    To recap, our holding does not turn on the delay in the

process of using the Puerto Rico courts; their procedures have not



     12   While mindful of the Supreme Court's statement in
Rosewell regarding the scope of the TIA's exception, see supra at
17, we also heed its qualification that "prior federal equity
cases" may still prove "instructive on whether a state remedy is
'plain, speedy and efficient.'" 450 U.S. at 525 n.33.


                                  - 26 -
been shown to be inadequate.           Nor do we rely on any concept of

inefficiency.    But by enacting the Fiscal Sustainability Act's $3

million annual cap on judgments exceeding $20 million and adopting

Treasury guidelines that prioritize other debts over tax refunds,

Puerto Rico has chosen to severely restrict the ability of its

courts to provide adequate remedies to Wal-Mart PR.

            The Secretary argued below and on appeal that Puerto

Rico's ability to offer a refund is immaterial because Wal-Mart PR

can, if successful in Puerto Rico court, have any past overpayment

applied to its future tax obligations.          Two credits are available.

First, section 6021.02 of Puerto Rico's Internal Revenue Code

provides: "When a payment in excess of any taxes imposed by [the

relevant title] has been made, the amount of such payment in excess

shall be credited, by request of the taxpayer or on the initiative

of   the   Secretary,   .   .   .   against   any   taxes   imposed   by   this

Code . . . , and any remainder shall be immediately refunded to

the taxpayer."      P.R. Laws Ann. tit. 13, § 33022(a)(1).                  The

district court, however, found that this credit applies only to

"payment in excess of any taxes imposed" and so is not available

where a taxpayer pays an amount actually then due but is later

entitled to a refund because the "taxes imposed" were illegal.

The Secretary offers no contrary view on appeal and so has waived

any argument that the first credit is an available remedy in Wal-

Mart PR's case.


                                     - 27 -
             Second, the Secretary cites another section of Puerto

Rico's Internal Revenue Code, which provides for a minimum tax

credit.   P.R. Laws Ann. tit. 13, § 30202.            The language of the

statute   is    circular,   but    the   undisputed   interpretation   the

district court adopted is that a taxpayer who has paid AMT in prior

years (because its tentative minimum tax exceeded its ordinary tax

liability in those years) may credit this AMT against its tax

obligations in years in which its ordinary tax liability exceeds

its tentative minimum tax.           In any year in which this credit

applies, however, the credit is capped at 25% of the amount by

which the taxpayer's ordinary tax liability exceeds its tentative

minimum tax in that year. The district court found that the Fiscal

Sustainability Act's $3 million annual recovery cap applies to

this credit, and neither party argues on appeal that this finding

was error.     The second credit thus suffers from precisely the same

inadequacy as does the tax refund option: under either remedy,

Wal-Mart PR will not be made whole for decades, if even then.

             We stress again that we do not hold that a mere delay in

recovery renders a remedy inadequate.        In normal course, one would

not be surprised that it might take several years to litigate a

refund claim and collect the judgment. The Supreme Court has held,

for example, that a two-year delay with no interest does not render

a state remedy inadequate.        See Rosewell, 450 U.S. at 520–21.    Wal-

Mart PR's case, therefore, might be very different if it faced a


                                    - 28 -
$21 million overpayment that might take seven years to collect at

$3 million per year.        Where one draws the line, we need not say

other than that twenty-three years is on the other side.

            3.   PROMESA

            We take judicial notice of the fact that, since the

district court's March decision, Congress has passed PROMESA,

which     attempts   to    address   Puerto   Rico's   fiscal   crisis   by

establishing the Financial Oversight and Management Board ("the

Board") and a process for Puerto Rico to restructure its debt.13

PROMESA § 101(a), (b)(1).       The parties agree that PROMESA does not

affect the jurisdictional analysis under the Butler Act.           Neither

party asserts that PROMESA's stay provision applies to this lawsuit

or that the Board has the power to grant the relief that Wal-Mart

PR seeks.    We likewise agree, for the two reasons already noted.

            First, PROMESA's stay provision does not apply to this

case.     Section 405 provides for an automatic "stay," effective on

the date of the Act's enactment, of certain judicial actions "with

respect to a Liability."        Id. § 405(b).    PROMESA's definition of

"Liability," however, includes only "bond[s], loan[s], . . . or

other financial indebtedness for borrowed money." Id. § 405(a)(1).

The remedy that Wal-Mart PR seeks -- relief from payment of future



     13   We asked the parties for supplemental briefing on
PROMESA's effect, if any, on the Puerto Rico federal district
court's jurisdiction to hear this case.


                                     - 29 -
taxes -- does not constitute money that Puerto Rico has borrowed.

It rather constitutes future potential tax revenue.               Because this

suit will not force Puerto Rico to pay any amount of money to Wal-

Mart PR, section 405's stay provision is inapposite.

             Second, the Board cannot grant the relief that Wal-Mart

PR seeks.      Under section 201, the Board must approve a Fiscal Plan

that "provide[s] a method to achieve fiscal responsibility and

access to the capital markets."            Id. § 201(b)(1).    That Plan must,

however, respect the Commonwealth's "relative lawful priorities"

that    were     in   effect   prior    to    PROMESA's      enactment.       Id.

§    201(b)(1)(N)     ("A   Fiscal   Plan    developed    under   this    section

shall . . . respect the relative lawful priorities or lawful liens,

as    may   be   applicable,    in   the     constitution,    other   laws,   or

agreements . . . in effect prior to the date of enactment of this

Act.").     Accordingly, PROMESA appears to grant no power to the

Board to repeal or amend the Fiscal Sustainability Act, which

continues to cap payments of court judgments at $3 million per

year and continues to grant Puerto Rico discretion not to pay even

that amount depending on the availability of funds that year.                 Nor

does it appear to allow the Board to repeal or amend the Treasury

guidelines, which "prioritize some government payment obligations

over others" but make "no provision . . . to prioritize the payment

of a court judgment ordering a tax refund."              Wal-Mart P.R., Inc.,

2016 WL 1183091, at *30.        If anything, a purpose of PROMESA is to


                                     - 30 -
increase Puerto Rico's tax revenues.14          Ultimately, PROMESA does

not change the almost certain likelihood that Wal-Mart PR will not

recover its tax debt if it complies with the transfer-based AMT

first and then seeks relief through the tax-refund process.              And

that near certainty of nonrecovery suffices to make the local

remedy inadequate and justifies the exercise of federal district

court jurisdiction to issue injunctive relief.          See Rosewell, 450

U.S. at 516–17 & n.21.

C.   Comity

           The   Secretary   argues    that    the   principle   of   comity

independently    compelled   the    district    court   to   abstain    from

exercising jurisdiction.      We review de novo.        See Esso Standard

Oil Co. v. Cotto, 389 F.3d 212, 217 (1st Cir. 2004) (citing Brooks

v. N.H. Sup. Ct., 80 F.3d 633, 637 (1st Cir. 1996)).

           "The comity doctrine counsels lower federal courts to

resist    engagement   in    certain    cases    falling     within    their

jurisdiction."    Levin, 560 U.S. at 421.       "Comity's constraint has

particular force when lower federal courts are asked to pass on



     14   As Wal-Mart PR points out, the two PROMESA provisions
directly addressing the Commonwealth's taxes both seek to increase
tax revenue.   Section 104(m) empowers the Board to "ensure the
prompt and efficient payment and administration of taxes through
the adoption of electronic reporting, payment and auditing
technologies."    PROMESA § 104(m).     Likewise, section 208(b)
requires the Governor to report to the Board "all existing
discretionary tax abatement or similar tax relief agreements."
Id. § 208(b).


                                   - 31 -
the constitutionality of state taxation of commercial activity."

Id.   Indeed, "the comity doctrine is more embracive than the TIA."

Id. at 424; see also Coors Brewing Co. v. Méndez-Torres, 678 F.3d

15, 22 (1st Cir. 2012) ("[E]ven if the TIA does not bar federal

court jurisdiction in certain classes of state tax challenges,

comity may require dismissal nonetheless."). Although we rely on

comity precedents that refer to states, our circuit has applied

comity considerations to Puerto Rico in the same way as we do to

states.    See, e.g., Torres-Rivera v. García-Padilla, 783 F.3d 42,

46 (1st Cir. 2015); Casiano-Montañez v. State Ins. Fund Corp., 707

F.3d 124, 129–30 (1st Cir. 2013).

            Comity is not an absolute bar to a federal district court

passing judgment on the lawfulness of a local tax.                 The Supreme

Court has repeatedly stated that comity bars federal district court

jurisdiction only insofar as the local court system affords an

adequate remedy.        See, e.g., Levin, 560 U.S. at 421 (stating that

comity limits federal jurisdiction "given that an adequate state-

court    forum    is    available"    to   adjudicate    the     claims);   Fair

Assessment in Real Estate Ass'n, Inc., 454 U.S. at 116 (comity

limits    federal      jurisdiction   "provided   of    course    that   [state]

remedies are plain, adequate, and complete"); Tully v. Griffin,

Inc., 429 U.S. 68, 73 (1976) (comity limits federal jurisdiction

"except in cases where an asserted federal right might otherwise

be lost").       The Supreme Court has also suggested that adequacy of


                                      - 32 -
the state system for comity purposes is the same standard as

"plain, speedy and efficient" under the TIA (and, as a result, the

Butler Act).    Fair Assessment in Real Estate Ass'n, Inc., 454 U.S.

at 116 n.8.

           As such, the same analysis we applied to the Butler Act

applies to the comity doctrine on these facts.             When the Supreme

Court stated in Levin that the restraint on federal jurisdiction

under the comity doctrine is broader than that under the TIA, it

was referring to a matter that is not at issue here: a case in

which a federal court seeks not to enjoin a state tax but instead

to increase a commercial competitor's tax burden.           Levin, 560 U.S.

at 417.   Such a case does not trigger the TIA because the requested

relief does not "disrupt the flow of tax revenue" to the state.

Id. at 419.      Nonetheless, the Supreme Court held that comity

concerns restrained federal jurisdiction over such a case because

of the limited "remedial competence" of the federal court relative

to the state court.        Id. at 428.     The concern in such a situation

is that upon the finding of an unlawful tax classification,

increasing     the   tax    burden    on    the    competitor   requires   an

interference with the state's tax code, an act that the state court

is "better positioned" to conduct.                Id. at 429.   Our circuit

applied Levin's reasoning to a similar situation in Coors Brewing

Co., 678 F.3d at 24.




                                     - 33 -
           The same is not true here because the requested relief

is invalidation of the tax, and, because the Butler Act does not

apply, that remedy is equally available in state and federal court.

In other words, the federal district court has equal remedial

competence as the Puerto Rico courts in this case.        Accordingly,

Levin and Coors Brewing Co. are inapposite, and the Secretary's

reliance on those cases is misplaced.      Even if the standards were

different, we would reach the same conclusion about comity.        The

Puerto Rico legislature has chosen to limit the competence of its

courts to effectuate relief.    Comity does not bar this action.

           Having cleared the threshold obstacles, we can proceed

to the merits of this appeal.15

                  IV. The Dormant Commerce Clause

           On the merits, the question is whether, as the district

court held, the amended AMT violates the dormant Commerce Clause.

The district court held a bench trial, so our review of its factual

findings   are   for   clear   error,    although   we   review   legal


     15   As a final matter before we reach the merits, the
Secretary also makes some challenges to the district court's
management of the case. But those challenges are meritless. It
was within the power of the district court to defer a decision on
the Secretary's Rule 12(b)(1) motion until jurisdictional
discovery could be conducted. Valentin, 254 F.3d at 363 n.3. To
the extent that the Secretary contests the district court's denial
of its requested discovery, we find no abuse of discretion, see
Braga v. Hodgson, 605 F.3d 58, 59 (1st Cir. 2010), in the district
court's decision that the information the Secretary was seeking
was irrelevant to the question before the court.



                                - 34 -
determinations de novo.         Wine & Spirits Retailers, Inc. v. Rhode

Island, 481 F.3d 1, 4 (1st Cir. 2007).

             The dormant Commerce Clause is an implied limitation

from   the        Commerce    Clause     that    "precludes         States       from

'discriminat[ing]       between      transactions     on    the    basis    of   some

interstate element.'"          Comptroller of Treasury of Md. v. Wynne,

135 S. Ct. 1787, 1794 (2015) (alteration in original) (quoting

Bos. Stock Exch. v. State Tax Comm'n, 429 U.S. 318, 332 n.12

(1977)).    As such, "a State 'may not tax a transaction or incident

more heavily when it crosses state lines than when it occurs

entirely within the State.'"           Id. (quoting Armco Inc. v. Hardesty,

467 U.S. 638, 642 (1984)).            Although we rely on cases that refer

to "states," we have held that the dormant Commerce Clause applies

to Puerto Rico in the same way that it applies to states.                  Walgreen

Co. v. Rullan, 405 F.3d 50, 55 (1st Cir. 2005); United Egg

Producers v. Dep't of Agric., 77 F.3d 567, 569 (1st Cir. 1996).

             In    applying    the    dormant   Commerce     Clause,       we    first

determine    whether     a    law    "discriminates    on    its    face    against

interstate commerce."           United Haulers Ass'n, Inc. v. Oneida-

Herkimer Solid Waste Mgmt. Auth., 550 U.S. 330, 338 (2007).                      If we

determine that the law is facially discriminatory, it is "virtually

per se . . . invalid[]," id. (quoting City of Philadelphia v. New

Jersey, 437 U.S. 617, 624 (1978)), and is permissible only upon "a

showing that the State has no other means to advance a legitimate


                                       - 35 -
local purpose," id. at 338–39 (citing Maine v. Taylor, 477 U.S.

131, 138 (1986)).

          It is indisputable that the amended AMT discriminates:

it taxes only cross-border transactions between a Puerto Rico

corporate taxpayer and a home office or related entity outside of

Puerto Rico.    The district court held that the amended AMT was

facially discriminatory.   We agree.

          The   Secretary's   argument,    as   articulated   at   oral

argument, appears to be that the AMT does not facially discriminate

against interstate commerce because it does not apply to particular

interjurisdictional transfers but is instead merely a component in

calculating an annual tax formula.        But even if we accept that

argument, the practical effects of the AMT demonstrate that it is

unconstitutionally discriminatory.      Whether or not the AMT is one

component in a broader tax scheme, the AMT nonetheless applies

only to interjurisdictional transfers within a corporate family.

The resulting "differential treatment of in-state and out-of-state

economic interests that benefits the former and burdens the latter"

is discriminatory.   Family Winemakers of Cal. v. Jenkins, 592 F.3d

1, 9 (1st Cir. 2010) (quoting Or. Waste Sys., Inc. v. Dep't of

Envtl. Quality, 511 U.S. 93, 99 (1994)).

          The "internal consistency" test developed by the Supreme

Court confirms the AMT's discriminatory effect.      This test "looks

to the structure of the tax at issue to see whether its identical


                               - 36 -
application by every State in the Union would place interstate

commerce at a disadvantage as compared with commerce intrastate."

Wynne, 135 S. Ct. at 1802 (quoting Okla. Tax Comm'n v. Jefferson

Lines, Inc., 514 U.S. 175, 185 (1995), superseded on other grounds

by 49 U.S.C. § 14505).        The AMT fails the internal consistency

test because if every state were to adopt the AMT, multistate

corporations      doing   business     across     state     lines    would    be

disadvantaged     relative   to   corporations      whose    operations      are

consolidated in one state.        In such a world, the AMT's tangible-

property tax would preclude multistate corporations from enjoying

the functional integration,          centralization of       management, and

economies    of   scale   associated   with     their   interstate    business

model.16    See Wal-Mart P.R., Inc., 2016 WL 1183091, at *41 (citing

Princo Corp. v. Int'l Trade Comm'n, 616 F.3d 1318, 1335 (Fed. Cir.

2010) (en banc)).

            The Secretary's next argument is that even if the AMT is

discriminatory on its face or in effect, it survives dormant

Commerce Clause scrutiny because it is "a proxy for the tax that

would be imposed upon profits that are shifted to related parties."


     16   Wal-Mart PR also relies on the "external consistency"
test, under which we examine "the economic justification for the
State's claim upon the value taxed, to discover whether a State's
tax reaches beyond that portion of value that is fairly
attributable to economic activity within the taxing State."
Jefferson Lines, Inc., 514 U.S. at 185.     We do not reach the
question of whether the AMT is discriminatory under this test as
well.


                                   - 37 -
The Secretary is correct that Puerto Rico has a legitimate interest

in ensuring that multistate corporations are appropriately and

proportionately    taxed    based     on   their   activities       within    each

jurisdiction in which they operate.            Cf. Container Corp. of Am. v.

Franchise   Tax   Bd.,   463   U.S.   159,     164-65    (1983).      While    the

Secretary admitted at the evidentiary hearing that there was no

reason to believe that Wal-Mart PR had actually been engaging in

abusive profit-shifting, the general problem of artificial profit-

shifting by multistate corporations is the object of a legitimate

state interest.

            However, if the AMT is to pass muster under the dormant

Commerce Clause, the Secretary must also show that there is "no

other means to advance [the] legitimate local purpose."                  United

Haulers Ass'n, Inc., 550 U.S. at 338–39 (citing Taylor, 477 U.S.

at 138); see also Or. Waste Sys., Inc., 511 U.S. at 101 ("cannot

be adequately served by reasonable nondiscriminatory alternatives"

(quoting New Energy Co. of Ind. v. Limbach, 486 U.S. 269, 278

(1988))); Hughes v. Oklahoma, 441 U.S. 322, 337 (1979) ("the

strictest scrutiny of . . . the absence of nondiscriminatory

alternatives").    This the Secretary cannot do.

            The   amended      AMT    is   a     blunt     and     unnecessarily

overinclusive approach to combatting profit-shifting abuse.                    It

essentially   establishes      an    irrebuttable       presumption    that    all

intercorporate transfers to a Puerto Rico branch from related


                                     - 38 -
mainland entities are fraudulently priced to evade taxes. In fact,

the Secretary all but admits that there are narrower alternatives

that target profit-shifting.17     One example is a unitary tax system

that uses a formula to distribute multistate corporations' income,

for tax purposes, to different jurisdictions.       Another example is

the already existing set of regulations "that authorize the Puerto

Rico Treasury to conduct a traditional transfer-pricing audit of

interstate transactions between related parties and to adjust

specific transfer prices . . . to recapture [improperly shifted]

profits."18   Wal-Mart P.R., Inc., 2016 WL 1183091, at *43.        Having

identified    numerous   less   restrictive   alternatives   to   advance

Puerto Rico's legitimate local purpose, we hold that the AMT is a




     17   In listing these possible alternatives, we do not decide
that any of those particular alternatives are themselves
sufficiently narrow to survive dormant Commerce Clause scrutiny.
It suffices for our purposes to say that the availability of those
less restrictive alternatives invalidates the AMT in its current
form.
     18   The Secretary asserts that those alternatives are
administratively infeasible for Puerto Rico and that the AMT was
the only practical way to combat abusive transfer pricing. But it
would be a perverse outcome if the resource and administrative
limitations of the Puerto Rico Treasury required us to hold that
the otherwise unconstitutional AMT passes constitutional muster.
At a minimum, Puerto Rico could cease to apply the tangible-
property tax to transfers of goods from a mainland Wal-Mart to
Wal-Mart PR in which Wal-Mart PR pays nothing for the transaction
and so could not possibly be engaging in improper profit-shifting.
The existence of these various alternatives is sufficient to
invalidate the AMT under the dormant Commerce Clause.


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facially   discriminatory   law   that     does   not   survive   heightened

scrutiny under the dormant Commerce Clause.

                            V.    Conclusion

           In light of the foregoing, we need not decide whether

the AMT also violates the Federal Relations Act or the Equal

Protection Clause.

           We affirm.




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