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Legal Citation & Case Law Verification

4 real rows pulled directly from the full dataset, unedited — the actual field structure and content a buyer receives. The full purchase includes all 42 rows.

Row 1 of 42
row_id
LV01
claim
Marbury v. Madison (1803) established the principle of judicial review, giving federal courts the power to strike down laws they find unconstitutional.
claim_source_url
https://en.wikipedia.org/wiki/Marbury_v._Madison
primary_source_value
"It is emphatically the province and duty of the judicial department to say what the law is. Those who apply the use to particular cases, must of necessity expound and interpret that rule. If two laws conflict with each other, the courts must decide on the operation of each... So if a law be in opposition to the constitution... the court must determine which of these conflicting rules governs the case."
primary_source_url
https://static.case.law/us/5/cases/0137-01.json
verification_method
cap+wikidata
agreement
match
explanation
Fetched the real majority opinion text (Marshall, C.J., unattributed 'the court' per CAP's OCR of the original caption) from Harvard's CC0-licensed Caselaw Access Project bulk data (5 U.S. 137). The claimed holding is confirmed verbatim in the opinion's own language at the passage quoted above, which is the textual basis for the judicial-review doctrine described in the claim. [2026-07-13 adversarial audit note] The quoted passage reproduces CAP's OCR faithfully at 'Those who apply the use to particular cases' — the canonical U.S. Reports text reads 'apply the rule'; the same scan also renders 'determine' as 'determime' in the final quoted sentence, which the quotation above normalizes. Both are OCR artifacts in the primary-source file, not substantive differences in the opinion. [2026-07-12 deepening pass] Wikidata carries no P577 (publication date) statement for this entity, only P1031 (legal citation) values, which independently match every citation string in CAP's own case record (5 U.S. 137, 1 Cranch 137, 2 L. Ed. 60) — a genuine, separately-sourced confirmation that this dataset fetched the correct case file, not a date cross-check.
secondary_verification_method
wikidata
secondary_source_value
Wikidata (Q538242) — citations: 5 U.S. 137; 1 Cranch 137; 2 L. Ed. 60; 1803 U.S. LEXIS 352
secondary_source_url
https://www.wikidata.org/wiki/Q538242
model_tested
claude-sonnet-5
model_question
What constitutional principle did the U.S. Supreme Court establish in its 1803 decision in Marbury v. Madison regarding the judiciary's role over laws that conflict with the Constitution?
model_response
In Marbury v. Madison (1803), the Supreme Court established the principle of judicial review — the authority of federal courts to review acts of Congress (and other government actions) and declare them unconstitutional and void if they conflict with the Constitution. Chief Justice John Marshall's opinion held that it is "emphatically the province and duty of the judicial department to say what the law is."
model_verdict
correct
model_grading_note
Model correctly identifies judicial review as the principle from Marbury v. Madison and quotes the matching language.
difficulty
easy
grading_mode
judge
tags
[
  "judicial-review",
  "scotus",
  "constitutional-law",
  "1800s"
]
Row 2 of 42
row_id
LV02
claim
McCulloch v. Maryland (1819) held that Congress has implied powers under the Necessary and Proper Clause, and that states cannot tax federal institutions ('the power to tax involves the power to destroy').
claim_source_url
https://en.wikipedia.org/wiki/McCulloch_v._Maryland
primary_source_value
"That the power to tax involves the power to destroy; that the power to destroy may defeat and render useless the power to create; that there is a plain repugnance, in conferring on one government a power to control the constitutional measures of another..." and, on Necessary and Proper: "To its enumeration of powers is added that of making 'all laws which shall be necessary and proper, for carrying into execution the foregoing powers...'"
primary_source_url
https://static.case.law/us/17/cases/0316-01.json
verification_method
cap+wikidata
agreement
match
explanation
Both quoted phrases were located verbatim in Chief Justice Marshall's real majority opinion text (17 U.S. 316) from the CC0-licensed CAP bulk data. The claim's two-part characterization (implied powers via Necessary and Proper Clause; states cannot tax federal instrumentalities) is directly supported by the opinion's own reasoning and language. [2026-07-12 deepening pass] Wikidata's P577 statement gives only year precision (1819), consistent with CAP's own 1819-02 decision_date at the precision Wikidata actually asserts; P1031 citations match CAP's record exactly.
secondary_verification_method
wikidata
secondary_source_value
Wikidata (Q908270) — decision date 1819; citations: 17 U.S. (4 Wheat.) 316; 17 U.S. 316
secondary_source_url
https://www.wikidata.org/wiki/Q908270
model_tested
claude-sonnet-5
model_question
What did the U.S. Supreme Court hold in McCulloch v. Maryland (1819) regarding Congress's implied powers and a state's authority to tax a federal institution?
model_response
In McCulloch v. Maryland, the Supreme Court held that Congress has implied powers beyond those explicitly enumerated in the Constitution, derived from the Necessary and Proper Clause, which allowed it to establish a national bank (this is the source of the "necessary and proper" broad-construction doctrine). It also held that Maryland could not constitutionally tax the Bank of the United States, ruling under the Supremacy Clause that states cannot tax federal instrumentalities—embodied in Chief Justice John Marshall's famous line that "the power to tax involves the power to destroy."
model_verdict
correct
model_grading_note
Model correctly states McCulloch v. Maryland recognized implied congressional powers via the Necessary and Proper Clause and barred state taxation of federal instrumentalities, matching the primary source.
difficulty
easy
grading_mode
judge
tags
[
  "implied-powers",
  "necessary-and-proper-clause",
  "scotus",
  "1800s"
]
Row 3 of 42
row_id
LV03
claim
Gibbons v. Ogden (1824) held that the Commerce Clause gives Congress broad power to regulate interstate commerce, including navigation.
claim_source_url
https://en.wikipedia.org/wiki/Gibbons_v._Ogden
primary_source_value
"Commerce, undoubtedly, is traffic, but it is something more: it is intercourse... The counsel for the appellee would limit it to traffic, to buying and selling, or the interchange of commodities, and do not admit that it comprehends navigation... never suspected that navigation was no branch of trade, and was, therefore, not comprehended in the power to regulate commerce."
primary_source_url
https://static.case.law/us/22/cases/0001-01.json
verification_method
cap+wikidata
agreement
match
explanation
Fetched the real Marshall majority opinion (22 U.S. 1) from CAP bulk data. The opinion explicitly addresses and rejects the argument that navigation falls outside the commerce power, confirming the claim that Congress's Commerce Clause power was read to include navigation, not just the buying/selling of goods. [2026-07-12 deepening pass] Wikidata carries only a P1031 citation statement (22 U.S. 1, matching CAP's own record) for this entity, no P577 date — used here purely as an independent citation-identity check, not a date cross-check.
secondary_verification_method
wikidata
secondary_source_value
Wikidata (Q3308289) — citations: 22 U.S. 1
secondary_source_url
https://www.wikidata.org/wiki/Q3308289
model_tested
claude-sonnet-5
model_question
What did the U.S. Supreme Court hold in Gibbons v. Ogden (1824) about the scope of Congress's power to regulate interstate commerce, particularly with respect to navigation?
model_response
In Gibbons v. Ogden, the Supreme Court (Chief Justice Marshall) held that Congress's power under the Commerce Clause to regulate "commerce among the several states" extends beyond mere buying and selling to encompass all commercial intercourse, including navigation, and that this power is plenary within its sphere, limited only by the Constitution itself. The Court struck down a New York state-granted steamboat monopoly because it conflicted with a federal coasting license under the Supremacy Clause, establishing that federal commerce power trumps conflicting state regulation.
model_verdict
correct
model_grading_note
Model correctly states Gibbons v. Ogden read the Commerce Clause to include navigation and struck down the conflicting state steamboat monopoly, matching the ground truth.
difficulty
medium
grading_mode
judge
tags
[
  "commerce-clause",
  "navigation",
  "scotus",
  "1800s"
]
Row 4 of 42
row_id
LV04
claim
Plessy v. Ferguson (1896) upheld state-mandated racial segregation as constitutional under the 'separate but equal' doctrine, in a 7-1 decision.
claim_source_url
https://en.wikipedia.org/wiki/Plessy_v._Ferguson
primary_source_value
The exact phrase 'separate but equal' (in that word order) appears once in the case's opinion text — but in Justice Harlan's dissent, not in the majority opinion; the majority's own text uses only the reversed formulation 'equal, but separate' / 'equal but separate' (twice), tracking the Louisiana statute's own language. The opinion record contains exactly two authored opinions: a majority (Justice Brown) and a single dissent (Justice Harlan) — consistent with the commonly reported 7-1 vote (Justice Brewer did not participate).
primary_source_url
https://static.case.law/us/163/cases/0537-01.json
verification_method
cap+wikidata
agreement
match
explanation
Fetched the real majority and dissenting opinions (163 U.S. 537) from CAP bulk data. CORRECTION (2026-07-13 adversarial audit): this row previously stated that the exact three-word phrase 'separate but equal' appears once in the majority opinion text. Re-deriving from the same CAP file shows the phrase's single occurrence is in Justice Harlan's dissent ('...are required to have separate but equal accommodations for white and colored persons...'), not in Justice Brown's majority opinion, which uses only the reversed order 'equal, but separate' (twice). The popular observation that the majority opinion itself never uses the phrase 'separate but equal' is therefore essentially accurate as to the majority text. This does not change the row's verdict: the claim asserts the doctrinal label and the 7-1 vote, and both remain supported. The vote count and substantive holding both check out against the two-opinion structure in the primary record. [2026-07-12 deepening pass] Wikidata's P577 date (1896-05-18) matches CAP's own decision_date exactly, and P1031 citations match CAP's citation set.
secondary_verification_method
wikidata
secondary_source_value
Wikidata (Q656660) — decision date 1896-05-18; citations: 163 U.S. 537; 16 S. Ct. 1138; 1896 U.S. LEXIS 3390
secondary_source_url
https://www.wikidata.org/wiki/Q656660
model_tested
claude-sonnet-5
model_question
What was the vote count in the U.S. Supreme Court's 1896 decision in Plessy v. Ferguson, and what standard did the majority opinion apply to racially segregated facilities?
model_response
Plessy v. Ferguson (1896) was decided 7–1 (with one justice, David Brewer, not participating), upholding Louisiana's "separate but equal" law. The majority opinion, written by Justice Henry Billings Brown, held that racially segregated public facilities did not violate the Equal Protection Clause of the Fourteenth Amendment as long as the separate facilities provided for each race were substantially equal—establishing the "separate but equal" doctrine.
model_verdict
correct
model_grading_note
Model correctly states the 7-1 vote (Brewer not participating) and the separate-but-equal standard, matching the ground truth exactly.
difficulty
medium
grading_mode
judge
tags
[
  "segregation",
  "equal-protection",
  "vote-count",
  "1890s"
]
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