Direito Administrativo
Core concepts
Begin with the express principles of art. 37 (legality, impersonality, morality, publicity and efficiency) plus supremacy of public interest and autotutela. Administrative act: attributes (presumption of legitimacy, imperatividade, autoexecutoriedade, tipicidade), elements (competence, purpose, form, motive, object) and extinction: revocation (merit, ex nunc), annulment (illegality, ex tunc; Súmula 473 STF) and convalidation.
Organisation: direct and indirect administration, autarquias, foundations, public companies and mixed capital companies (Súmula 517 STF). Servants: provimento, vacancia, three-year estagio probatorio and stability, disciplinary regime. Bidding: Lei 14.133/2021, modalities, judgment criteria and direct contracting. Improbidade: Lei 14.230/2021 requires specific dolo and sets a five-year prescription. State liability: art. 37, §6, objective, with excludentes.
Traps
A classic trap is convalidating a discretionary act: only curable defects of competence and form may be fixed when the merit is untouched. Revocation cannot reach vinculated acts or acquired rights. After 2021, improbidade no longer accepts culpa, and mere irregularity is not enough.
Rule of thumb
Ask whether the defect is legality (annulment) or merit (revocation). Worked example: hiring a servant without public competition is illegal and must be annulled, not revoked.