This educational guide is based on the linked primary sources. It is not a Court publication, is not affiliated with the Court, and is not legal advice.
In brief
Overview
Oral argument before the Supreme Court took place at 10:06 a.m.
Background and question before the Court
What each side argues
Petitioners' Arguments
According to Secretary of Commerce, the Secretary preferred using the known 98 % accuracy method over an untested statistical model.
The Census Bureau told the Secretary that asking the question would yield actual answers for 22.2 million people at 98 % accuracy.
According to Respondents New York, et al., according to Respondents New York, et al., the model had not been generated; the Census Bureau asserted it could produce one.
Respondents' Arguments
According to Respondents New York, et al., according to Respondents New York, et al., the citizenship question would cause a decline in response rates among non‑citizens and Hispanics, harming the states and localities where they live.
Amicus and Other Arguments
According to United States House of Representatives, the House stresses that accuracy of the decennial census is of utmost importance and that anything that undermines the accuracy of the enumeration is a problem.
According to MR. LETTER, the Justice Department can obtain citizenship information elsewhere and should not undermine the accuracy of the enumeration.
According to GENERAL FRANCISCO, disclosure‑avoidance protocols apply to all census data, including the citizen voting‑age population.
According to GENERAL FRANCISCO, empowering any group to boycott the census would be problematic.
What happened at oral argument
Chief Justice Roberts asked whether the alleged illegality is a predictive factor for standing.
According to Justice Sotomayor, justice Sotomayor referenced a “determinate or coercive effect” in her questioning.
According to JUSTICE KAGAN, justice Kagan noted that many arguments do not appear in the Secretary’s decision memo.
Chief Justice Roberts asked whether the citizenship question would help voting‑rights enforcement.
Justice Ginsburg asked whether any prior cases showed the Department would be aided by the citizenship question.
Justice Alito asked whether the Secretary’s choice was arbitrary given the lack of statistics for the model.
Justice Sotomayor asked how much accuracy the proposed question would achieve.
- [1] e20e8dd0239298076a8c-r1-5b4f4d8944f1e827.pdf, p. 10
- [2] e20e8dd0239298076a8c-r1-5b4f4d8944f1e827.pdf, p. 12
- [3] e20e8dd0239298076a8c-r1-5b4f4d8944f1e827.pdf, p. 31
- [4] e20e8dd0239298076a8c-r1-5b4f4d8944f1e827.pdf, p. 46
- [5] e20e8dd0239298076a8c-r1-5b4f4d8944f1e827.pdf, p. 46
- [6] e20e8dd0239298076a8c-r1-5b4f4d8944f1e827.pdf, p. 69
- [7] e20e8dd0239298076a8c-r1-5b4f4d8944f1e827.pdf, p. 91
What the Court decided
Why it matters
According to United States House of Representatives, the decennial census is of utmost importance to the House, and anything that undermines the accuracy of the enumeration is a problem.
Chief Justice Roberts asked whether the citizenship question would help voting‑rights enforcement.
Terms to know
No glossary terms are available for this guide.
Primary sources
Read the source materials on the official site or open the immutable repository copy used for this guide.
- e20e8dd0239298076a8c-r1-5b4f4d8944f1e827.pdforal argument transcript
Guide generated September 26, 2026. Automated validation accepted this version.