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Research

Sources

A practical hierarchy for choosing treaty texts, laws, filings, polls, research, and reporting for different kinds of claims.

Source quality depends on the question being asked. A signed treaty can establish what governments agreed to. A poll can estimate what a defined population reported during a particular period. Neither source alone establishes what the agreement produced or why respondents answered as they did.

Primary sources first

For legal, diplomatic, or institutional claims, begin with the record itself: a treaty, statute, designation list, court document, filing, archived statement, or original polling release. Primary material reduces the risk that a summary has omitted a qualification, date, or legal condition.

Secondary sources still matter

Primary material often requires context. Congressional Research Service reports, archival diplomatic histories, peer-reviewed scholarship, and established reference works can explain background, consequences, and disagreement. Secondary analysis should be identified as analysis rather than presented as the original record.

Source hierarchy

Claim Start here Use with care
What an agreement says Signed text, official archive Later summaries that omit clauses or conditions
What the law or designation is Statute, regulation, agency list, court ruling Political labels without a named authority
What an organization disclosed Filing, audited report, official statement Estimates that do not identify their method
What a population reported Original poll release and questionnaire Headlines that omit wording, dates, or sample
What happened on a date Official record and reputable contemporaneous reporting Retrospective claims without documentation
What an event means Serious historical or academic analysis A single source presented as settled consensus

Polling pages should link to original releases and follow disclosure practices such as those from AAPOR and Pew Research Center. Diplomatic history should lead to original texts, the State Department’s Office of the Historian, or relevant CRS products.

A citation should support the full factual claim attached to it. If it supports only part of a sentence, the sentence should be narrowed or supported with an additional source.