Saved copy of

Reply in support of application 26A305

U.S. Department of Justice, Office of the Solicitor General · 2026-09-10

Back to source details

The saved file is a PDF document of 0.2 MB. What follows is the text taken from it, which is the text the story quotes.

Jump to the cited passage

No. 26A305

In the Supreme Court of the United States

───────────

UNITED STATES POSTAL SERVICE, ET AL., APPLICANTS

STATE OF CALIFORNIA, ET AL.

───────────

DONALD J. TRUMP, ET AL., APPLICANTS

LEAGUE OF WOMEN VOTERS OF MASSACHUSETTS, ET AL.

───────────

REPLY IN SUPPORT OF APPLICATION FOR STAY

───────────

D. JOHN SAUER
Solicitor General
Counsel of Record
Department of Justice
Washington, D.C. 20530-0001
SupremeCtBriefs@usdoj.gov
(202) 514-2217

---

TABLE OF CONTENTS

A. The Government Has A Strong Likelihood Of Succeeding On
The Merits Of The Rule’s Legality .......................................................... 4

B. The Serious Irreparable Harms The Government Is Suffering
Warrant A Stay ...................................................................................... 16

---

In the Supreme Court of the United States
───────────

No. 26A305

UNITED STATES POSTAL SERVICE, ET AL., APPLICANTS

STATE OF CALIFORNIA, ET AL.

───────────

DONALD J. TRUMP, ET AL., APPLICANTS

LEAGUE OF WOMEN VOTERS OF MASSACHUSETTS, ET AL.

───────────

REPLY IN SUPPORT OF APPLICATION FOR STAY

───────────
This Court should swiftly stay the district court’s baseless injunction barring

the Postal Service from fully enforcing the Rule’s modest envelope-design and ad-

dressee-information requirements for federal-election ballot mail. Those require-

ments are a straightforward exercise of the Postal Service’s ordinary authority to

adopt mail-preparation rules designed to ensure that mail (especially sensitive mail)

is properly delivered to the intended recipient. The intended recipient is determined

entirely by the sender States, as the Rule’s requirements do not in any way displace

state law regarding voter eligibility or the manner of voting. Every day that the dis-

trict court’s injunction remains in place, more ballots are being sent through the U.S.

Mail without the benefits that the Rule provides for election integrity. This is causing

the precise irreparable injury that this Court already recognized when staying the

district court’s first baseless injunction to block implementation of such a rule, see

(1)

---

2

Trump v. California, No. 26A124, 2026 WL 2473573, at *4 (U.S. Aug. 4, 2026) (per

curiam), and States are facing an increasingly tighter window to ensure that their

envelopes comply with the Rule’s requirements if a stay is ultimately granted.

The Rule is a lawful exercise of USPS’s express statutory authority to regulate

the design of envelopes and the information needed about addressees, and thus it is

a constitutional implementation of Congress’s power to regulate the use of the federal

mails—or alternatively, its power to regulate the manner of federal elections. Re-

spondents fail to meaningfully rebut that basic premise. Their emphasis on the fact

that the postal statutes do not explicitly mention “election mail” is inconsistent with

Congress’s decision to grant the Postal Service general rulemaking powers with re-

spect to the preparation and delivery of all types of mail, including election mail and

other types of sensitive mail that present unique issues warranting specific prepara-

tion requirements. Likewise, respondents miss the mark in trying to distinguish the

Postal Service’s other exercises of analogous types of rulemaking authority over par-

ticular categories of mail, including election mail and other matter that is mailable

but sensitive in various ways. Respondents offer a scattershot of factual and policy

distinctions that have no grounding in the text of the rulemaking statutes.

Indeed, what animates much of respondents’ arguments is an objection, not to

the Rule’s requirements per se, but rather to the application of the Rule this year.

That approach erroneously conflates the merits with their equitable arguments. If

the Rule were only taking effect in 2030, States had four years to obtain the requisite

envelopes, and USPS had four years to test the portal and verification process, re-

spondents could not seriously claim that the Postal Service was exceeding its statu-

tory authority, much less unconstitutionally usurping state regulation of elections,

merely by requiring barcodes on ballot envelopes and verification that those barcodes

---

3

match voters to whom the States themselves intended to send ballots. Respondents

fear, however, that the process will not work when rolled out in a shorter period of

time this year, and that some voters may thus lose the privilege of voting by mail.

But critically, whether these envelope-design and addressee-information require-

ments fall within the Postal Service’s statutory authority turns on the legal text of

the rulemaking provisions, not the factual circumstances of how the Rule may be

implemented.

Signaling the weakness of the district court’s injunction, the state respondents

offer two alternative grounds to support the injunction, including an arbitrary-and-

capricious challenge to its implementation this year. But this Court should not deny

a stay by trying to rehabilitate an injunction in an emergency posture by invoking

distinct claims that no lower court has adopted; and regardless, those belated argu-

ments are even more meritless (which perhaps explains why even the district court

did not adopt them). Among other things, both arguments contravene Congress’s

express limitations on judicial review—first in exempting the Postal Service from the

APA, and second in channeling review of certain procedural claims to the Postal Reg-

ulatory Commission and its administrative-review scheme.

Turning to the equities, respondents essentially contend that the government

suffers no irreparable harm from the injunction because voter fraud is not sufficiently

common to be important. That remarkable claim cannot be reconciled with either

this Court’s earlier stay of the district court’s first injunction, or this Court’s recogni-

tion that even the threat of voter fraud “can undermine public confidence in the fair-

ness of elections” and that “fraudulent votes dilute the right of citizens to cast ballots

that carry appropriate weight.” Brnovich v. Democratic Nat’l Comm., 594 U.S. 647,

672 (2021); see Crawford v. Marion Cnty. Election Bd., 553 U.S. 181, 196-197 (2008).

---

4

Accordingly, the district court’s injunction imposes grave irreparable injury by re-

stricting implementation of modest measures that will help prevent and restrain po-

tential gross abuses of the mails to perpetrate a fraud on the Nation.

Conversely, respondents fail to justify the proposition that their asserted coun-

tervailing harms alone could support denying a stay. They cannot dispute that, if the

Rule were concededly lawful, then they would have no equitable basis for protection

from those asserted but lawful harms. After all, if the district court had simply issued

a preliminary injunction based on those harms alone, while taking no position on the

Rule’s legality or even admitting the Rule was lawful, that would be clear reversible

error. See Starbucks v. McKinney, 602 U.S. 339, 346-347 (2024); Winter v. NRDC,

555 U.S. 7, 20-22 (2008). The district court cannot avoid a stay of its injunction

merely by further tacking on conclusory, and demonstrably wrong, assertions that

the Rule exceeds the Postal Service’s statutory and constitutional authority.

In short, this is not the kind of “close case[ ]” in which “balanc[ing] the equities”

is decisive. See National Republican Congressional Comm. v. Brown, No. 26A274,

2026 WL 2618462, at *1 (Sept. 4, 2026) (per curiam). Rather, it is one where the

government’s “show[ing] that it is likely to succeed on the merits and that it is likely

to suffer irreparable harm without a stay”—“the most critical” factors—is so clear

that balancing is unwarranted. See California, 2026 WL 2473573, at *2. Accordingly,

this Court should stay the injunction as soon as possible, so that all involved can

immediately take the necessary steps for implementation of the Rule.

A. The Government Has A Strong Likelihood Of Succeeding On The
Merits Of The Rule’s Legality

1. At the outset, respondents resist application of the ultra-vires standard

for non-statutory judicial review of statutory claims that this Court most recently

---

5

applied in NRC v. Texas, under which they must demonstrate that the Postal Service

took action “entirely in excess of its delegated powers and contrary to a specific pro-

hibition in a statute.” 605 U.S. 665, 681 (2025) (emphasis and quotation marks omit-

ted); see Leedom v. Kyne, 358 U.S. 184, 188 (1958). Like the district court, they con-

tend that this standard—which requires something like “a Hail Mary pass,” id. at

681-682—applies only where a plaintiff “sued outside an otherwise available judicial

review scheme,” California Br. in Opp. 23; see LWVMA Br. in Opp. 17-18. That is

incorrect. As the government explained, see Appl. 14-15, the Leedom v. Kyne stand-

ard applies to all attempts to “end-run … the limitations of judicial-review statutes.”

NRC, 605 U.S. at 681. Respondents offer no coherent rationale for their counterin-

tuitive position that a statute that eliminates judicial review altogether somehow tol-

erates more sweeping non-statutory review than a statute that merely channels dis-

putes to a particular forum. Rather, the heightened standard for ultra-vires claims

applies equally where, as here, Congress has expressly eliminated judicial review un-

der the APA. 39 U.S.C. 410(a); Mittleman v. Postal Regulatory Comm’n, 757 F.3d

300, 304-308 (D.C. Cir. 2014).

By contrast, respondents’ cited cases involving actions by the President are

inapposite. See California Br. in Opp. 23-24; LWVMA Br. in Opp. 18. Congress has

not purported to expressly eliminate judicial review of statutory claims against pres-

idential actions, like those at issue in cases like Trump v. Cook, 146 S. Ct. 2234, 2246-

2248 (2026), and Youngstown Sheet & Tube Co. v. Sawyer, 343 U.S. 579, 584 (1952).

Rather, as the California respondents acknowledge, the relevant “limit on APA re-

view” in those cases was merely “that the President is not an ‘agency’ subject to the

APA.” California Br. in Opp. 24. In other words, Congress in the APA simply did not

speak to judicial review of the President’s actions at all, see Franklin v. Massachu-

---

6

setts, 505 U.S. 788, 800 (1992) (noting “that textual silence”), and thus this Court held

that a pre-APA implied cause of action in equity remains available, see Cook, 146 S.

Ct. at 2251 n.2. Here, however, Congress expressly exempted the Postal Service from

APA review, 39 U.S.C. 410(a), so respondents cannot “end-run” that exemption, NRC,

605 U.S. at 681, unless the Leedom v. Kyne standard is satisfied, see Federal Express

Corp. v. U.S. Dep’t of Commerce, 39 F.4th 756, 763-764 (D.C. Cir. 2022)

Respondents’ objection that applying the Leedom v. Kyne standard would allow

USPS to “engage in hugely consequential actions” immune from judicial review, Cal-

ifornia Br. in Opp. 24, does little to advance their cause. The heightened ultra-vires

standard applies only to statutory claims; accordingly, constitutional challenges re-

main available, while claims raising rights created by Congress are appropriately

subject to limits on judicial review imposed by Congress.

Finally, the California respondents attempt to secure APA review by charac-

terizing the Rule as a “proceeding[] concerning the mailability of matter.” California

Br. in Opp. 22 (quoting 39 U.S.C. 3001(m)). As explained, see Appl. 22-23; pp. 12-13,

infra, the Rule does not render anything nonmailable, which alone forecloses the ar-

gument. Regardless, the rulemaking was not a mailability proceeding that would be

subject to section 3001(m). Rather, Postal Service regulations provide a specific pro-

cess for “[m]ailability proceedings,” which “are initiated upon the filing of an appeal”

with USPS, typically after USPS has detained a particular item as nonmailable. 39

C.F.R. 953.2; see 39 C.F.R. Pts. 952, 953. Congress addressed some procedures rele-

vant to such proceedings in its statutes governing particular nonmailable matter,

such as false representations or lotteries—including by specifying that APA review is

available for orders issued in such proceedings. See 39 U.S.C. 3005, 3007, 3012.

2. In all events, respondents’ claims fail under any standard. The state

---

7

respondents largely retreat from their constitutional arguments, see California Br.

in Opp. 4, 22, and the organizational respondents merely assert that the Postal Ser-

vice “has unconstitutionally exercised control over the manner in which states con-

duct elections,” LWVMA Br. in Opp. 30. They claim that because the Rule is moti-

vated in part by the Postal Service’s efforts to protect against voter fraud—in partic-

ular, to deter bad actors on the front end from using the federal mails to perpetrate

voter fraud, and to facilitate law-enforcement efforts to discover such mail frauds on

the back end—the Rule governs elections rather than mail. See id. at 30-31. That,

however, is a basic category error. For example, States, not the federal government,

have general police power to regulate both fraud against the elderly and the disposal

of corpses. See United States v. Morrison, 529 U.S. 598, 618 (2000). But that in no

way means that the Postal Service acts unconstitutionally when it adopts a special

mail-preparation rule to prevent cremated remains from getting lost in the mail, see

Appl. 16, or if it adopts a special mail-preparation rule to maintain better records of

who is sending mail to senior centers that have been targeted for mail-fraud schemes,

see Appl. 18. Rather, when parties choose to use the federal mails to deliver items,

they subject themselves to the federal rules governing mail preparation that Con-

gress has delegated the Postal Service general rulemaking authority to adopt. Re-

spondents are thus left only with their statutory arguments, all of which fail.

a. Respondents offer little response with respect to the actual text of the

Postal Service’s rulemaking authorities. Congress authorized USPS “to adopt,

amend, and repeal such rules and regulations, not inconsistent with this title, as may

be necessary in the execution of its functions,” 39 U.S.C. 401(2), and granted it “all

other powers incidental, necessary, or appropriate to the carrying on of its functions

or the exercise of its specific powers,” 39 U.S.C. 401(10). The latter powers include

---

8

the power “to provide for the collection, handling, transportation, delivery, forward-

ing, returning, and holding of mail, and for the disposition of undeliverable mail.” 39

U.S.C. 404(a)(1). That authority plainly encompasses a rule requiring the use of In-

telligent Mail barcodes on envelopes and a process to verify that envelopes are being

sent to the addressees intended by the sender. If this Rule involved a category of mail

other than election mail, no one would have batted an eye over the legality of such

ordinary mail-preparation requirements—as, in fact, no one did when requirements

that are not materially different legally were adopted in the past for other types of

sensitive mail. See Appl. 16-17.

Respondents nonetheless contend that because the relevant statutes do not

“mention mail ballots,” the Rule is unauthorized. California Br. in Opp. 10. That

gets the nature of a general grant of authority exactly backwards, and it fails to

acknowledge that mail ballots are, by nature, a type of “mail”—precisely what the

statutes address. On respondents’ theory, all of applicants’ examples of regulations

governing particular types of mail—the use of election-mail-specific policies, the rep-

lica-explosives rule, the cremated-remains rule, and the hypothetical rule imposing

preparation conditions on mailings to senior centers—would all be unlawful, since

Congress did not confer specific authority to regulate those particular types of mail.

While respondents assert superficial distinctions in an attempt to carve out those

examples and claim that the Rule has “no historical precedent,” California Br. in Opp.

12; see LWVMA Br. in Opp. 28, each distinction fails, as detailed below.

b. Most importantly, Respondents cannot distinguish the Postal Service’s

other election-specific practices (for which they themselves have advocated, see Appl.

20). Under those practices, USPS has provided that absentee balloting materials

“must not be detained or treated as unpaid mail” and must be “promptly dispatched

---

9

and delivered to the addressees” even if a mailer does not affix the necessary postage.

USPS, Postal Operations Manual § 171.3, available at https://perma.cc/HY9N-TJ6Q.

Similarly, it has adopted practices to accelerate the delivery of ballot mail, even when

the sender has paid for a slower level of service. USPS, Kit 600: Official Election Mail

Guide, https://about.usps.com/kits/kit600.pdf, at 4. Respondents dismiss those prac-

tices because they are “voluntary” and do not result in the rejection of election mail.

California Br. in Opp. 13-14; LWVMA Br. in Opp. 24. But those distinctions are im-

material. As respondents fail to dispute, the text of Congress’s general grant of rule-

making authority to USPS does not distinguish between mandatory and permissive

rules (election-specific or otherwise), and there is no indication that Congress in-

tended that USPS have only the power to issue parchment rules with which it could

not mandate compliance.

For the same reason, respondents gain nothing by emphasizing that the Rule

is different (and not “modest”) because its “most significant feature” is that “USPS

will refuse to deliver ballots” whose envelopes are non-compliant. California Br. in

Opp. 14. Failure to follow any number of mail-preparation rules—e.g., not including

the address “only on the side of the piece bearing postage,” Domestic Mail Manual

§ 602.1.2, https://pe.usps.com/text/dmm300/602.htm#1_0—can result in mail not be-

ing delivered. That does not mean that all rules governing the mail are converted

into election regulations if the mailpiece is election-related. And in all events, for

those who comply with its requirements, the Rule, like the Postal Service’s other elec-

tion-specific policies, “will help ensure proper handling, efficient processing, and

timely delivery of [federal-election ballots] to and from voters.” 91 Fed. Reg. 54,966,

54,974 (Aug. 26, 2026).

Respondents also suggest that Congress has generally authorized the Postal

---

10

Service to adopt election-mail-specific practices that facilitate voting by mail, but not

those that burden it. See California Br. in Opp. 14. Even setting aside the illusory

nature of that distinction as applied to the Rule, see Appl. 21-22, respondents’ char-

acterization of the statutory framework is incorrect. While respondents invoke the

National Voter Registration Act, the cited provision requires only that USPS offer

favorable postage rates to voter registration materials, not ballots. See California Br.

in Opp at 13 (citing 39 U.S.C. 3629). And they invoke the Uniformed and Overseas

Citizens Absentee Voting Act (UOCAVA), but the cited provision requires only that

ballots mailed pursuant to that statute be mailed even without postage. See ibid.

(citing 39 U.S.C. 3406(a)(1)). Indeed, if any implication were to be drawn from that

provision, it would be that Congress intended for USPS to mail UOCAVA ballots, but

not other ballots, without postage; yet in stark contrast to the flawed negative infer-

ence they draw from the statutory nonmailability provisions, see pp. 12-13, infra,

respondents are perfectly fine with the Postal Service wielding its general rulemak-

ing powers to excuse additional election mail from postage requirements. This ger-

rymandered position contravenes ordinary principles of statutory interpretation.

c. Respondents next attempt to distinguish the Postal Service’s replica-ex-

plosives and cremated-remains rules, suggesting that those rules are merely applica-

tions of 18 U.S.C. 1716(a), which renders “all explosives, hazardous materials, * * *

and all other natural or artificial articles, compositions, or material which may kill

or injure another, or injure the mails or other property,” to be “nonmailable matter.”

See California Br. in Opp. 18-20; LWVMA Br. in Opp. 22-23. But the salient point

about replica explosives is that they are not explosives and thus not expressly defined

as nonmailable material under 18 U.S.C. 1716(a). And cremated remains are not

“hazardous” in any sense that is material to the special rule adopted for them. Nor

---

11

can respondents shoehorn those examples into section 1716(a) by suggesting that rep-

lica explosives and cremated remains “threaten to ‘injure’ ” USPS workers or the

mails. California Br. in Opp. 19; see LWVMA Br. in Opp. 22. Replica explosives

plainly pose no threat of injury on their own, which is why USPS has addressed them

using its general rulemaking authority, rather than refusing to mail them outright.

See, e.g., Restricting the Mailing of Replica or Inert Explosives, 75 Fed. Reg. 282, 283

(Jan. 5, 2010). And the potential injury from cremated remains—i.e., that they might

leak out of standard packaging and damage postal machinery—is separately ad-

dressed by USPS’s general rule that powdered substances must be packaged in sift-

proof containers. See U.S. Postal Serv., Publication 52 § 451.2(b) (Aug. 2026),

https://pe.usps.com/cpim/ftp/pubs/Pub52/pub52.pdf. Among powdered substances,

cremated remains in particular pose no additional threat to USPS workers or ma-

chinery—instead, it is the unique concerns presented by the risk of losing the cre-

mated remains of a loved one that justify the requirement that senders use special

packaging and a trackable shipping product. See 90 Fed. Reg. 9843, 9843 (Feb. 19,

2025) (explaining that the cremated-remains rule will “improve visibility and en-

hance handling methods through processing and transportation”). That concern in

no way implicates section 1716’s nonmailability bars, but it falls well with the ordi-

nary mail-preparation issues that Congress delegated the Postal Service general rule-

making authority to address.

Moreover, if respondents were correct that section 1716 authorizes regulation

of any article that might “injure the mails” in the capacious sense that they portray

the term, that would only support the Rule here. If the risk that the Postal Service

may lose track of a loved one’s ashes somehow counts as “injuring the mails,” then

the risk that fraudulent ballots may be transmitted for a federal election surely also

---

12

“injures the mails,” by implicating that federal instrumentality in a practice that “un-

dermine[s] public confidence in the fairness of elections,” Brnovich, 594 U.S. at 672.

d. As for the government’s hypothetical mail-preparation rules dealing

with elder-abuse mail scams targeting retirement communities, see Appl. 18, re-

spondents suggest that such rules “could” be authorized by specific statutes other

than the Postal Service’s general rulemaking powers, see LWVMA Br. in Opp. 23;

California Br. in Opp. 20. But that too is incorrect. As the government already ex-

plained, the statutes respondents identify—39 U.S.C. 3001(d), (h)-(j), and 3005—do

not cover the hypothetical regulation. They prohibit certain forms of scam mail, such

as solicitations disguised as bills, 39 U.S.C. 3001(d); solicitations “implying any Fed-

eral Government connection, approval, or endorsement,” 39 U.S.C. 3001(h)-(i); solici-

tations for the purchase of services provided for free by the federal government, 39

U.S.C. 3001(j); or advertisements for certain lotteries, 39 U.S.C. 3005. They thus do

not authorize prophylactic design and registration requirements for all envelopes

used to send solicitations to particular retirement communities that have been tar-

geted for mail-fraud scams. Again, though, merely maintaining better records about

such mailings would fall within the heartland of the Postal Service’s general rule-

making powers.

3. Respondents are likewise wrong that the Rule creates a new category of

“nonmailable” matter. California Br. in Opp. 17-18; LWVMA Br. in Opp. 18-24. As

the government has explained, see Appl. 22-23, the Rule does not render anything

nonmailable—it merely requires that federal-election ballot mail be sent in envelopes

designed in a certain manner and with addressee information provided ahead of time.

Nor have respondents cured the basic logical fallacy in emphasizing that some of the

nonmailability provisions adopted by Congress impose conditions rather than out-

---

13

right bans on mailing. See California Br. in Opp. 17-18; LWVMA Br. in Opp. 21-22.

To repeat, the fact that Congress deemed some mailpieces “nonmailable” in general,

but then permitted them to be mailed if certain conditions were met, does not imply

that any additional condition imposed on any mailable material by USPS, pursuant

to its general rulemaking authority, somehow violates the nonmailability provisions.

Again, that approach would render the Postal Service powerless to address matters

like replica explosives or cremated remains, which are mailable matter that never-

theless may be mailed only on certain conditions. As for the Postal Service’s require-

ment that envelopes be addressed solely on the postage-bearing side of the envelope,

see p. 9, supra, respondents baldly assert that “basic postage formatting require-

ments have always been treated as different in kind from restrictions concerning the

mailability of specific materials.” California Br. in Opp. 21. Once more, that ipse

dixit assertion has no basis in the text of the Postal Service’s rulemaking authorities.

4. Respondents’ invocation of the major-questions doctrine similarly falls

flat. As the government has explained, Appl. 23-24, the Rule in no way regulates

voter eligibility, the States’ authority to regulate elections, or any other potentially

“economic[ally] or political[ly] significan[t]” matter that might trigger the doctrine.

Learning Resources, Inc. v. Trump, 607 U.S. 229, 246 (2026) (plurality opinion). Re-

spondents’ attempt to invoke the doctrine thus appears to rest on the premise that

any election-specific regulation that has effects on elections is so “politically signifi-

cant” that Congress must expressly authorize it. See California Br. in Opp. 14-16;

LWVMA Br. in Opp. 26-29. Again, however, that sweeping premise would doom all

manner of ordinary election-specific mail policies—including measures that respond-

ents themselves have advocated. See Washington v. Trump, 487 F. Supp. 3d 976,

980, 984 (E.D. Wash. 2020). Indeed, adopting design and tracking rules for the enve-

---

14

lopes containing federal ballot mail lies squarely within the Postal Service’s wheel-

house.

At times, respondents seem to suggest that the Rule implicates the major-ques-

tions doctrine because the purported difficulties they will face in complying for the

2026 elections create a risk of disenfranchisement, even if that risk would dissipate

for future elections. See LWVMA Br. in Opp. 28-29; California Br. in Opp. 14. But

that makes no sense. The Rule’s envelope-design and addressee-information require-

ments either fall within the text of the Postal Service’s rulemaking powers or they do

not—their coverage does not shift over time depending on the relative burdens of

compliance. Since the major-questions doctrine is ultimately a tool for construing the

scope of powers delegated to the Executive by Congress, e.g., Learning Resources, 607

U.S. at 242; Biden v. Nebraska, 600 U.S. 477, 504 (2023), it likewise cannot turn on

and off based on such factors. Instead, a challenge to the reasonableness of a rule’s

effective date based on potential compliance difficulties is a paradigmatic arbitrary-

and-capricious claim under the APA, see Motor Vehicle Mfrs. Ass’n v. State Farm Mut.

Auto. Ins. Co., 463 U.S. 29, 43 (1983), but Congress expressly exempted the Postal

Service’s rulemaking from APA review. See 39 U.S.C. 410.

5. Finally, the California respondents raise several entirely distinct claims

not considered by the district court. California Br. in Opp. 24-30. Given that this

Court is “a court of review, not of first view,” Cutter v. Wilkinson, 544 U.S. 709, 718

n.7 (2005), it would be imprudent to consider claims that no lower court has addressed

as an alternative basis for denying an emergency stay here. In addition, even when

reviewing a preliminary injunction on direct appeal, the D.C. Circuit has explained

that, because “the decision whether to grant a preliminary injunction is a matter of

discretion, not a question of right,” “it is for the district court to determine, in the first

---

15

instance, whether the plaintiffs’ showing on a particular claim warrants preliminary

injunctive relief.” Sherley v. Sebelius, 644 F.3d 388, 397-398 (D.C. Cir. 2011). For

example, a purely procedural claim—such as one of the claims that respondents try

to raise here—could present very different issues when determining whether the bal-

ance of equities supports a preliminary injunction. See Winter, 555 U.S. at 23.

In any event, respondents’ alternative claims fare no better. As for their claim

that the Rule is arbitrary and capricious under the APA, see California Br. in Opp.

25-28, that claim fails because, again, the APA does not govern the Postal Service.

Accordingly, respondents’ invocation (id. at 25) of Encino Motorcars, LLC v. Navarro,

579 U.S. 211, 221 (2016)—which held, in an APA case, that “an agency must give

adequate reasons for its decisions”—is inapplicable. And respondents’ assertion that

arbitrary-and-capricious review is nonetheless available when Congress has ex-

empted an agency from the APA, see California Br. in Opp. 28 n.9, is irreconcilable

with Vermont Yankee Nuclear Power Corp. v. NRDC, 435 U.S. 519, 557-558 (1978),

where this Court made clear that courts may not impose extra procedural require-

ments on agencies beyond those required by statute.

Nor can respondents pursue here their claim that the Rule is invalid because

USPS failed to follow the procedures for seeking an advisory opinion from the Postal

Regulatory Commission pursuant to 39 U.S.C. 3661. See California Br. in Opp. 28-

30. To begin, a plaintiff seeking to invoke that provision must present its objection

to the Commission—federal district courts lack jurisdiction to consider it. 39 U.S.C.

3662(a), 3663; New York v. Trump, 181 F.4th 132, 138 (D.C. Cir. 2026) (“The Postal

Commission review scheme contains all the hallmarks of a statutory scheme that

precludes district court jurisdiction.”); see ibid. (citing three other court of appeals

cases in “unanimous agreement”). Respondents cannot end-run that jurisdictional

---

16

bar by invoking Axon Enterprises, Inc. v. FTC, 598 U.S. 175, 191 (2023), and asserting

a “here-and-now injur[y],” see California Br. in Opp. 30 (quotation marks omitted).

In Axon, it was the allegedly unconstitutional administrative process itself that im-

posed the injury on the plaintiff. See 598 U.S. at 182, 191. Here, by contrast, it is

the Rule that imposes the alleged injuries, not the administrative-review process to

challenge the Rule. Because bringing this claim before the Commission as the statute

requires would cause respondents no independent harm, Axon is inapposite.

In any event, the claim also fails on the merits. The Postal Service was not

required to seek an advisory opinion, because the Rule does not make changes “in the

nature of postal services which will generally affect service on a nationwide or sub-

stantially nationwide basis,” as 39 U.S.C. 3661(b) requires. See 91 Fed. Reg. at

54,976. Respondents suggest that the Rule “will generally affect service” nationwide

because its “operational changes to how USPS processes mail ballots will have a

meaningful impact on USPS’ delivery of ballots nationwide.” California Br. in Opp.

28. But a Rule affecting less than “0.1%” of total mail volume, 91 Fed. Reg. at 54,976,

does not have a “meaningful impact” from a quantitative perspective. See Buchanan

v. USPS, 508 F.2d 259, 262 (5th Cir. 1975). Nor does the Rule qualitatively change

“the nature of postal service” on a “nationwide basis,” ibid.—rather, as explained, it

adopts modest envelope-design and addressee-information requirements for a narrow

subset of mail.

B. The Serious Irreparable Harms That The Government Is Suffering
Warrant A Stay

1. Contrary to respondents’ assertions, see California Br. in Opp. 30;

LWVMA Br. in Opp. 38-40, the district court’s order imposes serious irreparable harm

on the government. Indeed, this Court already so concluded when it stayed the dis-

---

17

trict court’s prior injunction barring USPS from enforcing the President’s Executive

Order by implementing any final rule for the 2026 elections: “The Government is

likely to suffer irreparable harm without a stay” “[b]ecause reversal of the District

Court’s judgment” against “a rule applicable to [respondent] States” “would come too

late for the 2026 midterms.” California, 2026 WL 2473573, at *4. Given that enjoin-

ing implementation of a hypothetical future regulation “deal[t] ‘a serious setback’ to

the Executive’s ‘goals’ while this litigation unfolds,” ibid., it necessarily follows that

enjoining implementation of the actual final Rule is an even more serious setback.

And that harm is worsening daily: Ballots are already being mailed in at least three

States, with more to begin in the coming days. See Appl. 29-30.

The government plainly has a strong interest in the prevention of voter fraud,

which “can affect the outcome of a close election” and “undermine public confidence

in the fairness of elections and the perceived legitimacy of the announced outcome.”

Brnovich, 594 U.S. at 672. The Postal Service’s Rule serves that interest in two ways:

It makes election fraud harder to commit and easier to catch. First, by requiring

state officials to submit a list of all of the recipients to whom they intend to send

ballots, it deters bad actors from mailing ballots to unauthorized voters; and second,

by creating a record of individuals to whom ballots were mailed, it facilitates investi-

gation of any irregularities after the fact by relevant authorities. See 91 Fed. Reg. at

54,969.

Both of those mechanisms serve an important interest in “orderly administra-

tion and accurate recordkeeping,” and they help to prevent and restrain fraud and to

safeguard “public confidence in the integrity of the electoral process.” Crawford, 553

U.S. at 196-197. Protecting against voter fraud is critically important to ensure that

“fraudulent votes” do not “dilute the right of citizens to cast ballots that carry appro-

---

18

priate weight.” Brnovich, 594 U.S. at 672. Moreover, “public confidence in the integ-

rity of the election process has independent significance,” and “the electoral system

cannot inspire public confidence if [insufficient] safeguards exist to deter or detect

fraud or to confirm the identity of voters.” See Crawford, 553 U.S. at 197 (quotation

marks omitted). Thus, regardless of whether voter fraud is common or uncommon, it

is critically important that the government enact such safeguards, which “encour-

age[] citizen participation in the democratic process” by fostering confidence in elec-

tion outcomes. Ibid. Respondents’ contention to the contrary—that the Rule is not

necessary to safeguard election integrity because USPS found it served important

interests even if voter fraud is uncommon, 91 Fed. Reg. at 54,969; see California Br.

in Opp. 32—cannot be squared with this Court’s repeated recognition that the gov-

ernment can and should take steps to protect against both fraud itself and the per-

ception of fraud, which undermines confidence in elections.

Respondents nonetheless suggest that because the injunction allows States to

voluntarily comply with the Rule, that somehow eliminates any harm to the govern-

ment. See California Br. in Opp. 31. That is wrong. The injunction still prohibits

the Postal Service from requiring compliance with its envelope-design requirements

and from performing any verification to ensure that it does not mail non-compliant

envelopes. Severely watering down the efficacy of the Rule is “a serious setback.”

California, 2026 WL 2473573, at *4.

2. While respondents heavily emphasize the countervailing harms that

they purportedly will suffer if the Rule takes effect, see California Br. in Opp. 33-40;

LWVMA Br. in Opp. 31-38, they provide no meaningful response to the government’s

argument that countervailing equities matter only in cases where the merits and ir-

reparable-injury factors are close, see Appl. 30-33. They contend that the government

---

19

argues that it “could rush out any election-related policy on the eve of an election, and

no matter how disastrous the consequences for voting rights and elections admin-

istration, no one would have a remedy in court.” California Br. in Opp. 30-31 (em-

phasis added). That attacks a straw man. The government has not made a Purcell-

style argument that election-proximity alone entitles it to a stay, wholly apart from

the strength of its position on the merits and on irreparable injury. If the government

in some hypothetical case could not show even a sufficient “likelihood” of satisfying

those “most critical” factors, then it would not be entitled to a stay. See California,

2026 WL 2473573, at *2. And even if it were a “close case[ ]” on those factors—e.g., if

the merits were a toss-up, or if it was debatable whether the harms could be miti-

gated—then “balanc[ing] the equities” would be appropriate in making the ultimate

judgment whether a stay were warranted. See Brown, 2026 WL 2618462, at *1; cf.

Winter, 555 U.S. at 22-23 (denying preliminary injunction based on balancing of eq-

uities in case where it was “unclear” whether the plaintiffs were likely to suffer irrep-

arable harm and where the court of appeals at times had suggested a mere “‘possibil-

ity’” of irreparable harm).

In the actual case here, by contrast, the government has made an overwhelm-

ing showing on both factors: This Court has already found serious irreparable harm

warranting a stay (and those harms are now even more serious), and the district

court’s reasons for enjoining the Rule (and respondents’ defense of that injunction)

are divorced from the statutory text of the Postal Service’s rulemaking power and

contrary to the Postal Service’s existing practice of adopting analogous types of mail-

preparation policies for sensitive categories of mail, including election mail. So if this

Court agrees with that assessment, then the question becomes whether respondents’

alleged countervailing harms from implementation of the Rule on the eve of the elec-

---

20

tions can alone defeat a stay of the injunction. And respondents offer no coherent

justification for that type of “reverse Purcell” principle, under which members of the

public get to violate a valid regulation for one last election courtesy of an improper

injunction. After all, the purported harms they face are lawful burdens of complying

with a lawful rule. Just as those harms alone could not have justified issuance of the

injunction in the first place, see Starbucks, 602 U.S. at 346-347; Winter, 555 U.S. at

20-22, they cannot justify shielding that injunction from a stay pending appeal now.

* * * * *

For the foregoing reasons and those stated in the government’s application, the

Court should stay the injunction of the United States District Court for the District

of Massachusetts pending the resolution of the government’s appeal to the United

States Court of Appeals for the First Circuit and any proceedings in this Court.

Respectfully submitted.

D. JOHN SAUER
Solicitor General
SEPTEMBER 2026