Program I · Jurisprudence — Public Pilot

The Comparative Jurisprudence Lab

Compare U.S. religious-liberty doctrine with international human-rights standards. Select a U.S. decision. Select a human-rights system. Every proposition is linked to the official source.

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Open methodology

STEP 1

Select a U.S. decision

U.S. Supreme Court or federal appellate decision

STEP 2

Select one or more human-rights systems

Choose the regional or universal system to compare against. Multiple systems may be selected.

STEP 3

Comparison

Comparison · Published · Dataset v2026.1

Groff v. DeJoy compared with European System · Universal System

600 U.S. 447 (2023) · 2023

The U.S. Standard

Holding

Title VII requires an employer denying a religious accommodation to show that the burden of granting it would result in substantial increased costs in relation to the conduct of its particular business. The Court clarified — but declined to overrule — its prior decision in Trans World Airlines, Inc. v. Hardison, rejecting the widely applied reading that any burden greater than a 'de minimis' cost sufficed to defeat an accommodation.

Controlling test

"Undue hardship" under Title VII, 42 U.S.C. § 2000e(j), means a burden that is "substantial in the overall context of an employer's business" — a fact-specific inquiry considering the accommodation's practical impact in light of the employer's nature, size, and operating cost. The prior "de minimis" gloss is displaced.

“We hold that showing "more than a de minimis cost," as that phrase is used in common parlance, does not suffice to establish "undue hardship" under Title VII. . . . [A]n employer must show that the burden of granting an accommodation would result in substantial increased costs in relation to the conduct of its particular business.”

Groff v. DeJoy, 600 U.S. 447, 468, 470 (2023) (slip op., at 18, 20)

The International Standard

European System

Eweida and Others v. the United Kingdom

ECtHR, Applications nos. 48420/10, 59842/10, 51671/10 and 36516/10, Judgment of 15 January 2013 (Fourth Section), final 27 May 2013

Governing test

Under Article 9 ECHR, a limitation on the manifestation of religion must be prescribed by law, pursue a legitimate aim, and be "necessary in a democratic society" — i.e. proportionate. The Court abandoned the earlier view that the ability to resign and find other work negated any interference; instead, that possibility is weighed within the overall proportionality balance, and a fair balance must be struck between the individual's rights and the interests of others.

“Given the importance in a democratic society of freedom of religion, the Court considers that, where an individual complains of a restriction on freedom of religion in the workplace, rather than holding that the possibility of changing job would negate any interference with the right, the better approach would be to weigh that possibility in the overall balance when considering whether or not the restriction was proportionate.”

Eweida and Others v. United Kingdom, § 83 (15 Jan. 2013)

Universal System

UN Human Rights Committee, General Comment No. 22 (Art. 18, ICCPR)

CCPR/C/21/Rev.1/Add.4 (30 July 1993); ICCPR Art. 18 (opened for signature 16 Dec. 1966, 999 UNTS 171)

Governing test

ICCPR Article 18 protects the freedom to manifest religion or belief, which may be limited only by limitations 'prescribed by law and . . . necessary to protect public safety, order, health, or morals or the fundamental rights and freedoms of others' (Art. 18(3)). General Comment No. 22 stresses that the internal freedom of thought, conscience and religion (the forum internum) admits of no limitation whatsoever, and that permissible restrictions on manifestation must be strictly construed and directly related and proportionate to the specific need.

“Article 18 distinguishes the freedom of thought, conscience, religion or belief from the freedom to manifest religion or belief. It does not permit any limitations whatsoever on the freedom of thought and conscience or on the freedom to have or adopt a religion or belief of one's choice. . . . Limitations may be applied only for those purposes for which they were prescribed and must be directly related and proportionate to the specific need on which they are predicated.”

HRC General Comment No. 22, §§ 3, 8 (1993)

Binding Mandates

Instrument	Provision	Nature of obligation	Who is bound
Title VII, Civil Rights Act of 1964	42 U.S.C. § 2000e(j); § 2000e-2(a)	Duty to reasonably accommodate an employee's religious observance or practice unless doing so imposes an undue hardship (post-Groff: substantial increased costs).	Covered employers (15+ employees), employment agencies, and labor organizations within the United States.
European Convention on Human Rights	Article 9(1)–(2)	Negative duty not to interfere with, and positive duty to secure, the freedom to manifest religion; limitations must be lawful, pursue a legitimate aim, and be proportionate.	The 46 Contracting States of the Council of Europe; enforceable against the State before the ECtHR.
International Covenant on Civil and Political Rights	Article 18(1)–(3)	Absolute protection of the forum internum; manifestation may be restricted only where prescribed by law and necessary and proportionate to an enumerated aim.	States parties to the ICCPR (173 as of the dataset date); supervised by the UN Human Rights Committee.

Key Concepts

Undue hardship (U.S.): Under Title VII after Groff, a burden that is substantial in the overall context of the employer's business — assessed on the facts, in relation to the employer's nature, size, and operating cost. The prior 'more than de minimis' reading no longer suffices.
Proportionality (European / Universal): The requirement that any restriction on a manifestation of religion be suitable, necessary, and strike a fair balance between the individual right and the competing public or private interest. Central to Art. 9 ECHR and Art. 18(3) ICCPR analysis.
Forum internum / forum externum: The inner freedom to hold or change a belief (forum internum), which is absolute and non-derogable, distinguished from the outward freedom to manifest belief in worship, observance, practice and teaching (forum externum), which may be subject to proportionate, lawful limits.
Margin of appreciation: The latitude the ECtHR affords national authorities in assessing local conditions and balancing competing rights, subject to European supervision of whether the measure was justified in principle and proportionate.
Reasonable accommodation: An adjustment to a workplace rule or practice that enables religious observance. Express and rule-based in U.S. statutory law; in the European and Universal systems it is generally addressed through the proportionality balance rather than a free-standing statutory duty.

Convergences

Both frameworks reject the notion that the mere availability of an alternative (changing jobs, or absorbing a trivial cost) automatically defeats a religious claim; each demands a substantive, fact-specific weighing.Groff v. DeJoy, 600 U.S. 447, 470–71 (2023); Eweida v. UK, § 83 (ECtHR 2013).
Both treat the burden of justification as resting on the party imposing the restriction — the employer under Title VII, the State under Art. 9 ECHR and Art. 18(3) ICCPR.Groff, 600 U.S. at 468–70; Eweida v. UK, §§ 84–85; HRC Gen. Comment No. 22, § 8.
Both recognize protection of religious manifestation in the employment/public sphere as a serious interest that cannot be displaced by administrative convenience alone.Groff, 600 U.S. at 470–72; Eweida v. UK, §§ 94–95; ICCPR Art. 18(1).

Divergences

The U.S. standard is a statutory employer-accommodation duty enforced between private parties; the European and Universal standards are human-rights obligations that primarily bind the State, reaching private employment indirectly through positive obligations.42 U.S.C. § 2000e(j); ECHR Art. 9; ICCPR Art. 18; Eweida v. UK, §§ 84, 91.
U.S. doctrine frames the question as 'undue hardship / substantial increased cost' to the employer; the international systems frame it as 'proportionality' of a limitation to a legitimate aim, an analytically distinct calibration.Groff, 600 U.S. at 468–70; Eweida v. UK, § 84; HRC Gen. Comment No. 22, § 8.
The international systems expressly insulate the forum internum from any limitation, a categorical protection with no direct analogue in the Title VII accommodation inquiry, which is confined to workplace practice.HRC Gen. Comment No. 22, § 3; ICCPR Art. 18(2); cf. Groff, 600 U.S. at 454–55.

Sources

Every document cited above, linked to its official repository. Each carries the destination domain and the date the Institute last verified the link.

How comparisons are built

Comparisons are drafted by the Institute under its published Documentation Standards. Sourcing, verification, citation, and abstention protocols are public and replicable.
Every proposition carries a pinpoint citation to an official primary source — slip opinions, treaty texts, court judgments, and treaty-body records — never a paraphrase presented as authority.
The dataset is versioned (currently v2026.1, updated 2026-01-08) and openly licensed under Creative Commons Attribution 4.0. It is identical for every user.
Corrections may be submitted publicly. The Institute accepts no commissioned or client-specific work; no comparison is adapted to, prepared for, or withheld from any particular reader.

Mission

A free, publicly accessible platform consolidating the law of religious liberty in the United States — Supreme Court and federal appellate doctrine, the constitutional and statutory protections of the fifty states, and Title VII with its interpretive materials — together with rigorously sourced documentation of the religious practices that recur in American litigation and workplace administration. Every user, from judicial chambers to a member of the public, consults the identical resource.

Comparative boundaries

The Lab's comparative dimension is deliberately bounded: U.S. constitutional and statutory authority is the exclusive governing framework for U.S. users; foreign and international materials appear solely as contextual and scholarly resources, consistent with their status in U.S. adjudication.