Diagnostic vs. Defensive Information Control: _A General Theory with Applications to Surveillance, Negotiation, Platform Design, and Peer Review_

This paper introduces a fundamental distinction between two structurally different forms of institutional information control: defensive (withholding information to protect a value, process, or entity) and diagnostic (withholding information to instrumentalize the resulting ignorance and generate observational data from the affected party’s behavior under epistemic constraint). While both forms create epistemic asymmetry, they have different legitimacy conditions, different temporal profiles, and different normative requirements. The paper derives from this distinction a specific normative constraint—the equalization principle—which holds that no manufactured diagnostic epistemic asymmetry may persist into consequential adjudicative, evaluative, or decisional processes without disclosure and contestability. The paper defends equalization against weaker alternatives (proportionality, ex post audit, aggregate notice, independent oversight) by arguing that the specific harm of diagnostic control is inferential subordination—the production of interpretations of the affected party’s own conduct that the affected party cannot inspect—and that only disclosure plus contestability addresses this harm at the correct structural level. The paper tests the principle across four domains: state surveillance, negotiation, platform design, and scientific peer review. In each domain, existing failures of justice and institutional legitimacy are traced to violations of the equalization principle. The paper also identifies a form of epistemic injustice—structural epistemic subjection—not captured by Miranda Fricker’s testimonial/hermeneutical taxonomy, and proposes equalization as its institutional remedy. The general conclusion is that the conditions for permissible institutional opacity are more demanding than typically recognized: any institution that manufactures ignorance for diagnostic purposes must specify the temporal boundary of the diagnostic phase, identify the equalization mechanism, and ensure contestability before consequential deployment of the diagnostic yield.