The three lines of defense model is a framework that describes the roles and responsibilities of different stakeholders in the risk management and internal control processes of an organization. The three lines of defense are:
The first line of defense: the operational management and staff who are responsible for identifying, assessing, and responding to the risks, as well as implementing and maintaining the controls within their areas of activity.
The second line of defense: the risk management, compliance, and security functions who are responsible for establishing the risk policies and standards, providing guidance and support, monitoring and reporting on the risk performance and compliance, and facilitating the risk management and internal control processes across the organization.
The third line of defense: the internal audit function who is responsible for providing independent and objective assurance on the effectiveness and efficiency of the risk management and internal control processes, as well as recommending improvements and best practices. The stakeholders who are typically included as part of a line of defense within the three lines of defense model are the legal team, who belong to the second line of defense. The legal team is responsible for ensuring that the organization complies with the relevant laws and regulations, aswell as for advising and assisting the organization on the legal aspects and implications of the risk management and internal control processes. References = Risk and Information Systems Control Study Manual, Chapter 1, Section 1.4.1, p. 32-33