From Notice to Contestable Grounds: Necessary Informational Conditions for Algorithmic Contestability

Notice, explanation, and an appeal procedure can leave an affected party unable to investigate an institution’s determination. Where contestability is independently required or promised, this article develops the Necessary Informational Conditions framework to identify what information must enable. It connects a material objection to the question that must be answered, the operations that could answer it, and a test of whether any adequate route can dispense with a candidate operation. Six functions organize the inquiry: determination and consequence; sociotechnical roles and evidence control; data, source, and quality; governing-standard-operation fit; evidential warrant, uncertainty, and threshold; and contextual applicability. Necessity is conditional on the task, an independently justified adequacy floor, and the feasible routes compared. Different documents or expert arrangements may perform the same operation; an adequate route that omits it defeats its necessity. The framework also specifies arrangements for making the work possible: baseline orientation, contemporaneous preservation, inquiry-activated access, protected mediation, and usable support. These must let affected parties discover what warrants investigation before they are expected to substantiate an objection. Meaningful contestability also requires timely institutional consideration through which evidence and reasons can affect the determination. K.W. v. Armstrong illustrates how obstacles to inquiry and review can interact. A proposed research program tests omission and substitution, compares rival classifications, and develops a contestability toolkit. The contribution is a common framework for diagnosing failures of inquiry, comparing remedies, and designing procedures through which affected people and their representatives can investigate consequential judgments and bring evidence and reasons to bear on them. Preprint, October 2026. A companion article, Private Power without Epistemic Preemption: Relational Institutional Answerability in Algorithmic Decision-Making, is in preparation.