How professional discretion develops: a co-evolutionary theory of teacher competence and institutional support

Professional development research identifies effective features—content focus, active learning, sustained duration—but cannot explain why identical interventions yield variable outcomes across schools. This gap matters: when systems cannot calibrate support to teachers’ developmental readiness, they grant autonomy before competence develops, producing adaptations that lower expectations, or constrain capable teachers, driving attrition. Existing theories treat teacher competence and organisational capacity as separate developmental tracks. We theorise they must co-evolve: as teachers investigate practice through disciplined inquiry, they generate knowledge enabling organisations to differentiate support; as organisations adjust structures, teachers develop capabilities earlier conditions could not accommodate. Professional discretion—the authority to exercise judgement matched to demonstrated competence—emerges from this reciprocal process. The framework specifies four developmental levels (pre-discretion, procedural, substantive, and innovative discretion) and corresponding organisational requirements, explaining variable professional development outcomes as alignment or misalignment between developmental readiness and institutional capacity. This co-evolutionary perspective resolves the autonomy-accountability impasse by reframing it: the policy challenge is not choosing between competing goods but calibrating both as competence develops.