The Coalition awarded $100m in sport grants that were not assessed on their merits in order to favour “targeted” Coalition seats at the May 2019 election, according to a scathing report from the Australian National Audit Office released on Wednesday.

The report, by auditor general Grant Hehir, slammed the handling of the program by the then sports minister, Nationals deputy leader Bridget McKenzie, finding she ignored the merit-based assessment undertaken by Sports Australia for almost half the successful projects.

The audit office found the successful applications were “not those that had been assessed as the most meritorious in terms of the published program guidelines”, finding McKenzie’s office had run a “parallel” assessment process in deciding how to hand out the funds.

Its report found there was a distributional bias in the award of grants.

“The award of funding reflected the approach documented by the Minister’s Office of focusing on ‘marginal’ electorates held by the Coalition as well as those electorates held by other parties or independent members that were to be ‘targeted’ by the Coalition at the 2019 Election,” the audit said.

“Applications from projects located in those electorates were more successful in being awarded funding than if funding was allocated on the basis of merit assessed against the published program guidelines.”

The $100m program was administered by the Australian Sports Commission, known as Sport Australia, with the guidelines saying eligible applications would be assessed competitively against the three weighted merit criteria.

However, Hehir found that the separate process undertaken by McKenzie’s office “drew upon considerations other than those identified in the program guidelines, such as the location of projects”. Her office “also applied considerations that were inconsistent with the published guidelines”, the auditor said.

“It was this assessment process that predominantly informed the Minister’s funding decisions, rather than Sport Australia’s process,” the audit said.

Sports Australia had ranked the projects after assessing each application for eligibility and against the three merit criteria to arrive at an overall assessment score.

The ANAO was tasked with examining the program after Labor questioned how the Liberal candidate for Mayo, Georgina Downer, was able to present a giant taxpayer-funded $127,373 cheque to the Yankalilla Bowling Club in February 2019.

The program, called the Community Sport Infrastructure Grant Program, was announced in 2018 to ensure more Australians had access to quality sporting facilities, encouraging greater community participation in sport and physical activity.

During a short application timeframe of just six weeks, Sport Australia received 2,056 project proposals seeking more than $396.6m.

Funding totalling $100m was awarded to 684 projects across three rounds in the months before the election, with the final round announced in April.

Hehir said that had a merit based process been followed, the cut-off score would have been 74 out of a possible 100. More than 400 projects received funding that were below this score, in defiance of recommendations made by Sports Australia.

The audit found that in each of the three rounds of funding, Sports Australia’s recommendations were not followed or even considered.

In the first round, 91 of the projects (41%) approved were not endorsed by the Sport Australia board. In the second round, 162 (70%) of the approved projects were not recommended, and in the final round 167 (73%) of the approved projects had not been recommended by Sport Australia.

The auditor found the design of the program was deficient in a number of areas. There was potentially no legal basis for the minister to approve successful projects, and “it is not evident to the ANAO what the legal authority was”, which it said was a “significant shortcoming”.

He found the guidelines were “well structured and included clear assessment criteria with transparent weightings”, even if these were ultimately ignored.

Labor’s shadow minister for sport, Don Farrell said McKenzie needed to explain the “betrayal” of the sports community that had been exposed in the audit.

“The Morrison government’s shameless politicisation of taxpayers’ money meant for community sports clubs is appalling, unacceptable and cannot go unpunished,” Farrell said.

A spokeswoman for McKenzie said it “was a very popular program that funded 684 projects right across the country to help get people up and moving.”

“All projects selected for funding were eligible to receive it.”

The explosive report comes just weeks after a separate audit of the government’s $220m regional jobs and investment packages program tabled on Melbourne Cup day found ministers knocked back almost 30% of recommended projects and supported 17% of those not recommended by the department.