The families of 800 people who died during Victoria's COVID-19 wave linked to a fatally flawed hotel scheme would be "gobsmacked" criminal charges have been dropped.
Spiros Vasilakis, whose mother Maria died in 2020 in aged care just days after testing positive to the virus, was outraged by the decision.
"It's a joke," Mr Vasilakis told AAP.
"Those of us who lost family, all of us would just be bewildered and gobsmacked."
A legal loophole has been blamed and Mr Vasilakis fears that could put other cases related to individual outbreaks at risk.
Several class actions are in the Supreme Court over COVID-19 outbreaks, including at aged care homes.
Mr Vasilakis is also worried it sends a message that there's "nothing to see here, move on".
"(It's) saying no one's responsible for those lives, when we know there were actual individuals responsible for allowing the virus to spread," he said.
WorkSafe charged the Department of Health in September 2021 with 58 breaches of the Occupational Health and Safety Act after a 15-month investigation into the bungled system.
But the case was canned days out from trial after the County Court threw out evidence unearthed during a separate judicial inquiry.
The charges were dropped on Tuesday, with the Office of Public Prosecutions not fighting a bid to abandon the proceedings.
"WorkSafe is deeply disappointed by the decision to discontinue criminal proceedings," a spokesperson said.
"As an independent regulator, WorkSafe strives to enforce the highest standards of health and safety for workers and the community it serves."
The case fell apart after an April 9 ruling by the County Court to exclude evidence produced by a judicial inquiry into the hotel quarantine scheme.
Ten witnesses provided statements to the inquiry, led by Judge Jennifer Coate, on the health department's behalf, and the court ruled that under legislation they could not be used as evidence in the criminal proceeding.
The prosecutors office opted not to appeal the decision and said it "substantially weakened" their case.
A spokesman for the office said it was determined there were not reasonable prospects of the charges producing a conviction.
The department was responsible for the state's first hotel quarantine program between March and July of 2020.
The judicial inquiry found 99 per cent of Victoria's second wave of COVID-19 cases could be traced to private security guards who became infected at the Rydges on Swanton and Stamford Plaza hotels in May and June 2020.
The second wave resulted in more than 18,000 new infections, 800 deaths and a lockdown that lasted 112 days.
"We’re pleased to see this matter resolved, avoiding a lengthy and costly trial in circumstances where there has already been a public inquiry into the hotel quarantine program," a Department of Health spokesperson said in a statement.
Opposition Leader John Pesutto questioned prosecutors' justification for abandoning the trial and said Victorians would be questioning why no one was being held accountable for the disastrous scheme.
"If evidence were not admissible that came out of the Coate inquiry, there are other ways you can adduce evidence in a criminal proceeding," he said.
Premier Jacinta Allan took aim at Mr Pesutto for casting shade on prosecutors.
"This was an decision by the independent (Office of Public Prosecutions)," she said.
"This is the same Liberal Party who said 'let it rip' - they wanted to not see any restrictions on the community."
In March 2023, a magistrate found there was sufficient evidence to support a conviction and sent the matter to the County Court for trial, which had been scheduled to begin on Monday.
