The State Parliament’s Penalty Rates and Fair Pay Select Committee was scathing of the effects of the cuts to Sunday penalty rates for retail and hospitality workers that began in July 2017, saying the reductions hurt the most vulnerable workers and had not achieved their stated goals.

But Opposition MPs on the committee attacked the inquiry as a waste of taxpayers’ money designed to help the Labor Party attack the Turnbull government’s industrial relations policies.

The committee’s final report, published on Tuesday, argues there is little or no evidence that the promised benefits of the cuts – more jobs and more hours for retail and hospitality workers – have materialised.

Instead, the committee’s chairwoman Labor MP Gabrielle Williams wrote, the reductions had hurt the standard of living of up to 147,000 workers in Victoria, particularly young employees and women.

“During the inquiry, it became clear that the reduction in penalty rates is already having a significant detrimental impact on thousands of workers in the affected industries, particularly women, young people and employees in rural and regional parts of the state,” Ms Williams wrote.

“These workers, many of whom are among Victoria’s lowest-paid, have had their take-home pay reduced at a time when cost of living pressures are rising.

“As further penalty rate cuts are implemented in coming years, these effects will be magnified.”

The committee cited evidence from Professional Pharmacists Australia which reported no increase in opening hours of pharmacies, or more pharmacists employed following the first penalty rate reduction.

While noting it has been less than 12 months  since the first penalty rates reductions took effect, "the anticipated benefits of the penalty rate reductions have been realised", the committee concluded.

But the committee was able to recommend little in the way of concrete action by the state government which has very limited influence on industrial relations policy.

Instead the Andrews government was urged in the committee’s report to “advocate” for changes to the Commonwealth’s industrial relations policies to protect the take-home pay and improve protections for workers.

The one recommendation where the state could act, the introduction of a criminal offence of knowingly underpaying workers, has already been promised if Labor wins November’s state election.

But the two Liberals on the committee, Robert Clark and Dee Ryall, wrote  dissenting report savaging their Labor and Greens’ colleagues motivations for holding the inquiry.

“This inquiry has been a blatant misuse of public funds by the Andrews government,” the two Liberals wrote.

“While the issues involved are important, the Victorian Parliament and government have almost no role in them.”

Mr Clark and Ms Ryall said the committee could not attract many witnesses other than those from the union movement who simply used the process to assert their policy positions.

“Most stakeholders have recognised the partisan motivation for this inquiry and its lack of genuine purpose,” the Liberals wrote.