Alongside personnel and methodical professionalism, the independence of external public auditing guarantees the important balanced, reliable and objective reporting on audit results. The independence of the ACA is therefore not only vital for the transparency of state administration, but also ensures an effective and lasting implementation of the control function of the parliaments by strengthening trust by the general public in state institutions.
The Lima Declaration of Guidelines on Auditing Precepts (INTOSAI 1977) requires supreme audit institutions to have organisational, functional and financial independence, to be anchored in the constitution and to have unlimited auditing control of all public resources. Further requirements concern unhindered access by auditors to all relevant documents, sufficient personnel headcount, the skills to audit organisations in which there is public participation, the authority to audit institutions receiving state grants and the right to submit reports to parliament and to the public and finally to have effective follow-up mechanisms.
These requirements for the independence of supreme audit institutions were repeated in the Declaration of Mexico, which was enacted on the occasion of the 2007 INCOSAI in Mexico City. In this, eight pillars were set out on which the independence of the supreme audit institutions is based. These eight pillars set out what is behind the independence of the SAIs and what is necessary to achieve it.