In response to the inquiry's closing submission, lawyers for Mikakos said it's "implausible" to suggest no one decided to use private security for the failed hotel quarantine program because it doesn't account for the realities of "governmental operation and decision-making."
Mikakos' response comes after counsel assisting the inquiry said the decision to use private security was "arrived at by way of a creeping assumption" that went unquestioned by several layers of government officials and agencies before the premier's press conference on March 27.
Andrews told the inquiry he couldn't recall why he mentioned private security at the press conference before the state control centre meeting on March 27.
At the time he said: "Police, private security, all of our health team will be able to monitor compliance in a much easier way, in a static location, one hotel or a series of hotels, as the case may be.
"That will mean that more of those police that we have, those 500 police that are doing that work in terms of coronavirus enforcement, they'll be able to get to even more homes where people are supposed to be quarantining."
But Mikakos rejected this, arguing: "Had the decision not already been made by that time, the Premier would not have announced the use of private security in the program."
"The weight of the evidence points clearly to an actual decision, not an assumed one," being made during or soon after a meeting of National Cabinet about midday on March 27.
A Victoria Police submission to the inquiry similarly argues the decision was made before the premier's press conference.
"It is open to the board to find that, by no later than this point, a decision had been made that the proposed model would involve private security and that all interested agencies understood this," the police submission says.
"For several hours, a model involving the use of private security was being developed without any consultation with Victoria Police, the Minister for Police or, it seems, the public health team."
The submissions from Victoria Police and Mikakos point to a message written by Chief Commissioner Graham Ashton at 1.32 p.m on March 27, describing the appointment of private security as a "deal set up" by the Department of Premier and Cabinet.
Further, Mikakos asserts that the reason why no one can identify the prime decision-maker for engaging private security was because Andrews subverted normal cabinet processes when he introduced the Crisis Council of Cabinet.
The range of contradictory views given by the premier and ministers to the hotel quarantine inquiry as to who had overall responsibility and accountability was caused by a failure to "follow ordinary Cabinet-led decision-making processes," the submission reads.
Andrew told reporters on Friday that he did not accept Mikakos' criticism but conceded it would ultimately "be a matter for the board [of inquiry] to report on."
The premier refused to answer questions, instead offering his familiar refrain that the inquiry was "an ongoing process" and he would wait for its final report before he makes any comment.
He said it was "not appropriate for me to predict" the inquiry's findings but assured Victorians that they could be confident he will take the necessary actions to address them.
"We won't hesitate to take up the findings," he said.
When asked if he had spoken to Mikakos since her resignation, he said: "Na."
But in her submission on Friday, Mikakos' lawyers assert that she played "no role in the critical decision to use private security in the frontline, or the terms on which they were contracted. Nor did her department."
"For those decisions, others must take responsibility."
Mikakos' lawyers also indicated they did not cross-examine Andrews or other ministers during the inquiry for fear it would be "politically disadvantageous" or "improper."
The inquiry, led by retired judge Jennifer Coate, is due to hand down its final report on November 6.