A government tender awarded to an Australian company was later taken away and given to German carmaker BMW last year.
The $6 million contract for armoured vehicles was originally won by Australian-based BAE Systems in 2012 to upgrade a Holden Caprice but the Government decided that the BAE/Holden deal was too risky.
The luxury BMW limousines were used to ferry world leaders including US President Barack Obama at the G20 in Brisbane last year.
At the time, the Government argued Holden had not tendered, but information released yesterday shows they had, were successful, but the deal was then scotched. After the new Government withdrew industry support, Holden announced it would stop making cars here in 2017.
The new details on the armoured cars come as the Government defends its decision not to put the $20 billion to $40 billion Future Submarines project out to tender, but rather to a "competitive evaluation process".
South Australian Senator Penny Wong, who had put a question to Attorney-General George Brandis about the process, said the answer showed the Government was waging an "irresponsible campaign against the Australian car industry".
"There are striking similarities with the Abbott Government's handling of submarines - excluding Australian suppliers, abandoning competitive procurement, and favouring foreign suppliers," she said.
Senator Brandis said the Government had received four tenders, two from Australian companies, and in December 2012 gave the gig to BAE to "up-armour" a Holden Caprice. "During the negotiation, it became increasingly apparent that the BAE Systems 'up-armoured' solution could not guarantee the required level of protection," he wrote.