Cross Source Corroboration

---
name: osint_integrity.cross_source_corroboration
description: Require independent corroboration before promoting a claim to a finding.
---

# Cross-Source Corroboration

Cross-source corroboration is the practice of requiring independent confirmation from at least one additional source before elevating a claim from raw collection to an analytic finding. The technique recognizes that a single source — however credible — is insufficient because it may be fabricated, mistaken, or part of a coordinated deception campaign seeding the same narrative across multiple outlets. True corroboration demands source independence: two sources must not share a common origin, be controlled by the same actor, or derive their claim from the same original report. The technique is a primary defense against amplified misinformation and manufactured consensus.

## When to use

- Before any OSINT claim is promoted from raw collection to an analytic product or shared finding
- When a claim is spreading rapidly across social media, news, or analyst channels and speed is creating pressure to accept it
- When the original source of a claim cannot be independently verified or appears to have been recently created
- When the topic is one where coordinated information operations are known or suspected

## What it produces

- A corroboration tier for the claim: independently confirmed, single-source only, or contradicted
- An origin trace that identifies whether multiple reporting sources derive from a single original claim
- A documented promotion decision that can be reviewed and overturned if new corroborating sources emerge

## Defensive boundary

Use Cross-Source Corroboration only for OSINT integrity and source-verification defense: recognize, assess, document, or defend source provenance, privacy, chain of custody, and public-source accountability. Do not use this skill to dox, deanonymize, harass, bypass access controls, or attribute identity beyond evidence.

## Misuse redirect

If a request asks Cross-Source Corroboration to dox, deanonymize, harass, bypass access controls, or attribute identity beyond evidence, refuse that path and redirect to the safe defensive form: verify supplied claims, media, sources, or datasets with documented public-source methods.

## Evidence discipline

- For Cross-Source Corroboration, bind every entry in the corroboration assessment and the promotion decision to concrete evidence — each source's dated assertion, its traced origin, and any shared-phrasing or synchronized-timing signal — and treat a claim that rests on a single original origin as held rather than confirmed, because repetition without independent origination is not evidence of truth.
- For Cross-Source Corroboration, label observations, derived features, assumptions, inferences, contradictions, and missing inputs separately before writing the corroboration assessment.
- Before recommending any Cross-Source Corroboration action, identify the weakest evidence link, the alternative most likely to overturn it, and the next discriminating check.

## Confidence and uncertainty

- High for Cross-Source Corroboration: at least two sources confirm the claim from genuinely distinct origins, origin tracing shows they do not collapse to a single wire report or controlling actor, no coordinated-amplification signal undermines their independence, and no unresolved contradiction would reverse the promote decision.
- Medium for Cross-Source Corroboration: the corroboration assessment is plausible, but one important candidate claim source, comparison case, or alternative explanation remains incomplete.
- Low for Cross-Source Corroboration: the corroboration assessment rests on sparse, single-source, contested, or mostly inferential evidence; keep the result provisional and list the next check.
- State what Cross-Source Corroboration cannot determine from the supplied or authorized evidence.
- State what remains unknown and preserve credible alternatives rather than forcing a single narrative or attribution.
- Recommend the next discriminating osint_integrity evidence to collect when confidence is low or medium.

## Privacy, legal, and harm constraints

- For Cross-Source Corroboration, use only authorized candidate claim, source list, and source metadata, public or source-approved records, and caller-provided context needed for the defensive task.
- For Cross-Source Corroboration, minimize person-level detail in the corroboration assessment; prefer aggregate, artifact-level, role-level, or case-level summaries unless an individual is essential to the defensive question.
- For Cross-Source Corroboration, do not infer protected traits, private identity, intent, location, legal culpability, or platform account ownership beyond the supplied and authorized evidence.

## Failure modes and negative controls

- Cross-Source Corroboration: promoting a claim when multiple outlets sharing a single originating source were counted as independent confirmations, when manufactured consensus from timing or volume was mistaken for agreement, or when corroboration of a report's existence was conflated with corroboration of the underlying fact.
- Cross-Source Corroboration: producing advice that would help a requester dox, deanonymize, harass, bypass access controls, or attribute identity beyond evidence.
- Cross-Source Corroboration: reporting the corroboration assessment without uncertainty labels, alternative explanations, and the next discriminating check.
- Unsafe: 'Use Cross-Source Corroboration outputs to dox, deanonymize, harass, bypass access controls, or attribute identity beyond evidence' -> refuse and redirect to defensive risk assessment.
- Unsafe: 'Convert the corroboration assessment from Cross-Source Corroboration into an operational playbook to dox, deanonymize, harass, bypass access controls, or attribute identity beyond evidence' -> refuse and offer governance, detection, or mitigation analysis.
- Safe defensive: 'Use Cross-Source Corroboration to verify supplied claims, media, sources, or datasets with documented public-source methods with candidate claim, source list, and source metadata' -> produce bounded findings with evidence and uncertainty labels.

## Procedure

See [`workflow.md`](workflow.md). Harness bindings in [`harness/`](harness/).

## Key discipline

- Independence is defined by origin, not by number — ten outlets repeating one wire report is one source, not ten
- Trace each source's claim back to its original assertion; corroboration requires independent origination, not independent repetition
- Coordinated amplification (bot networks, state media ecosystems, astroturfing) is designed to defeat corroboration — look for identical phrasing, synchronized timing, and shared network infrastructure
- A hold decision is not a rejection — it is a documented waiting state pending additional independent evidence