The merger of the federal immigration department and customs service has failed to deliver the expected budget savings or other benefits, a report says.
As well, dozens of consultants were used without properly checking value for money
The auditor-general examined the merging of the Department of Immigration and Border Protection (DIBP) and the Australian Customs and Border Protection Service between 2014 and 2017.
The new department and Australian Border Force started in July 2015, but then became the Department of Home Affairs last December.
"(The restructure) is not achieving commitments made to government in relation to additional revenue, and is not in a position to provide the government with assurance that the claimed benefits of integration have been achieved," the audit report found.
Based on progress to the end of December 2017, the department was predicted to only collect 31.6 per cent of the additional customs duty revenue to which it committed in the integration business case.
Its record keeping was described as "poor" and there was "no evidence identified to indicate that written briefings were provided to the minister (Peter Dutton) on progress throughout the implementation process".
As well, almost half of the department's senior executive service level officers who were there in July 2015, no longer worked at the department two years later, leaving a huge gap in corporate memory.
The audit found extensive use was made of consultants, but proper evaluations did not occur in 94 per cent of cases of contracts valued at more than $1 million.
"Therefore it is unclear whether these services represented value for money," the report found.
Labor immigration spokesman Shayne Neumann said it was one of a series of scathing reports relating to Mr Dutton's portfolio.
"If the Minister for Home Affairs is so out of his depth when it comes to managing his department, why has Malcolm Turnbull granted him unprecedented powers over Australia's domestic security agencies?" Mr Neumann said.
The Home Affairs Department agreed to a series of recommendations to improve its contract management and record keeping, as well as a "benefits realisation plan".
Department first assistant secretary Mark Brown disputed some of the financial conclusions in the report, as well as "statements made in regard to project management and overall visibility of the Executive in relation to the integration project".
