"It's not a question of being legally prohibited,"he said."No one's ever asserted that ... but I cannot conduct a judicial inquiry from this podium while there is another judicial inquiry being conducted."
The Premier refused to answer questions about what conversations he had in the cabinet room with Health Minister Jenny Mikakos,Jobs Minister Martin Pakula and Police Minister Lisa Neville,whose departments were most involved with the hotel quarantine program.
Mr Andrews said on June 30"a number"of Victoria's second wave of infections could be linked to hotel quarantine,but a fortnight later,Chief Health Officer Brett Sutton said it was conceivable security guards were responsible for most,if not all,of new infections.
The Premier again refused on Thursday to commit to releasing the genomic sequencing that showed how hotel quarantine could have triggered Victoria's second wave,sending the state into stage three and four lockdowns.
Mr Andrews said"at least a significant portion"of Victoria's cases had come from hotel quarantine,but it was the Health Department's prerogative to release the genomic sequencing report,not his.
"I would need to speak with the people who do that testing and hold that data,"he said.
Opposition Leader Michael O'Brien said Victorians deserved clarity on who was responsible for"what will probably wind up to be the biggest public policy failure in this country's history".
"Victorians need confidence that the ministers in charge of the pandemic response are up to the job,"he said.
"The Premier says the buck stops with him. Well it's not just him. It's his government ... we need to know they are up to the job and until those questions are answered,Victorians don't have confidence and won't have confidence."
Professor Cheng said on Thursday that after Victoria recorded 20 cases on June 25 and 200 cases on July 11,a continuation of that trajectory without restrictions would have resulted in 2000 cases by July 27 and 20,000 cases by August 12.
"Clearly we're not getting the 2000 cases but the numbers at the moment are certainly too high,"said Professor Cheng,who added that the impact of Melbourne and Mitchell Shire's stage four restrictions would become clear in seven to 10 days.
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