• The statutory purpose, stated in the Act's short title and opening language, is to "provide a definition of death for the purposes of the law of South Australia" (short title and s 2). Treated as a claim: the Act provides a clear legal trigger (brain cessation or circulatory cessation) to be used across State law.

• Costs and incentives: the Act imposes no explicit fees or administrative levies, but it creates operational consequences. Because the statute declares the conditions that legally constitute death (s 2) but does not prescribe diagnostic procedures, the practical costs fall to medical and administrative systems that must establish and document those conditions in practice. Those actors bear the compliance and evidentiary burden of translating the statutory words into routine practice.

• Trade‑offs and opportunity costs: by adopting a brief, high‑level definition (s 2) the Act reduces statutory ambiguity about the legal standard but transfers the work of specifying procedures to other instruments (clinical protocols, registration rules, or case law). The trade is legislative simplicity in return for reliance on external professional or administrative rules to manage implementation.

• Implementation risk and discretion: because the Act does not define "irreversible" or the tests for "cessation of all function of the brain" or for circulatory cessation (s 2), there is room for medical judgment, institutional protocols, and ultimately judicial interpretation to decide difficult cases. That creates potential for variation in practice and for disputes that may require court resolution.

• Effects on private choice and private actors: the Act constrains when private legal rights and obligations tied to death can be exercised by setting the legal trigger (s 2). It does not itself alter private contracts or estates, but it determines the event (death) that activates those arrangements and thus affects when people and organisations can act under law.

Concentration of benefits and diffuse costs

• The Act centralises a single, uniform legal definition for all State law uses (s 2). Any concentrated benefit from this—such as clearer legal predictability for particular parties—flows from having a statutory trigger rather than relying solely on non‑statutory practice. The costs of operationalising that trigger (medical assessments, recordkeeping, dispute resolution) are dispersed across medical providers, registrars and courts because the Act is silent on procedural detail and these actors must supply it.

Summary of who pays, who decides, and what behaviour changes (source citations)

• Who pays: the Act contains no financial provisions; practical costs arise from implementing the definition in medical and administrative practice (see s 2).
• Who decides: the Act sets the legal standard (s 2) but does not name the decision‑maker or prescribe tests; decision‑making and diagnostic procedures are left to medical, administrative and judicial actors to adopt or interpret (inferred from the absence of procedural detail in s 2).
• Behaviour changes: actors who must confirm or act on death (medical practitioners, registrars, courts, and private parties that rely on death being established) will apply the statutory criteria in s 2 when determining whether the legal condition of death has occurred.

(Act text: Short title and section 2.)