The need for an Excess Vote arises when a department has incurred expenditure or other use of resources upon an existing service beyond the amounts authorised for it during the financial year in question, or where there is no proper parliamentary authority for the service.
When the exact amount of the excess expenditure or other use of resources has been ascertained on the completion of the audit of the Departmental Resource Accounts, the Comptroller & Auditor General makes a report to the House. His findings come before the Committee of Public Accounts, which, after an examination of the explanation provided by the department-in-question, submits its own report to the House, setting out the reasons and stating any objections (if any) to the excess being approved.
This inquiry therefore will call in front of the Committee the department(s) which have incurred expenditure beyond the amounts authorised for it and will examine and report on the issues involved.