One of Scott Morrison's final acts as Prime Minister was to instruct the Australian Border Force (ABF) to publicise an interception of a suspected asylum seeker boat on election day.
This decision is now subject to an inquiry by Home Affairs Department Secretary Mike Pezzullo.
While the ABC approached former prime minister Scott Morrison about the matter, he declined to comment.
As voters were going to the polls on Saturday, the Operation Sovereign Borders Commander issued a rare statement announcing a "vessel has been intercepted in a likely attempt to illegally enter Australia from Sri Lanka".
The ABC can reveal that the highly-controversial move during the election caretaker period followed a direct request from the Prime Minister's Office to publicly release details of the sensitive ABF operation before it had been completed.
During his final press conference - held in the early afternoon of election day - the then prime minister was asked about reports emerging that morning about a boat arrival.
"Well, I can confirm that, that there has been an interception of a vessel en route to Australia. That vessel has been intercepted in accordance with the policies of the government and they're following those normal protocols," Morrison told reporters in Sydney.
About the same time as the prime minister spoke, the statement from Rear Admiral Justin Jones, the Operation Sovereign Borders Commander, appeared on the ABF's website, warning that the Australian government's policy on illegal boat arrivals "remains unchanged".
"We will intercept any vessel seeking to reach Australia illegally and to safely return those on board to their point of departure or country of origin," Rear Admiral Justin Jones said in the five-line statement requested by Morrison's office.
The unusual disclosure of operational "on water matters" is now subject to an inquiry by Home Affairs Department Secretary Mike Pezzullo, ordered this week by the new Labor government.
Officials with knowledge of the events that occurred on Saturday say the Department of Home Affairs first examined the legality of issuing a statement during an election campaign because of concerns it could breach caretaker conventions and politicise the public service.
Australian voters across the country have received "news alert" texts stating an illegal boat has been intercepted and advising voters to "keep our borders secure by voting Liberal".
Eventually, it was decided that a statement could be issued by the commander, a move that has been privately criticised by Rear Admiral Jones' colleagues in the Australian Border Force as well as the Australian Defence Force.
Shortly after public confirmation of the boat arrival, the Liberal party sent mass robo-text messages to voters in marginal seats, urging them to back the government and its tough border policies.
The ABC has approached former prime minister Scott Morrison, specifically to ask why his office requested the Australian Border Force to reveal the boat interception, but he has declined to comment.
The Department of Home Affairs has also said it would be "inappropriate to comment on the matter" because the new Labor government has now ordered a review into the circumstances of the ABF statement.
On Tuesday, Rear Admiral Justin Jones confirmed the boatload of asylum seekers intercepted near Christmas Island on election day had now been returned to Sri Lanka fter appropriate assessments.
-ABC