Journalist Mark Willacy has won the $80,000 Prime Minister's Literary Award for non-fiction with his groundbreaking account of SAS war crimes in Afghanistan.
The book, titled Rogue Forces, is based on accounts from Australia's elite special forces soldiers who broke their code of silence to speak to him.
"I'm elated, I'm surprised because it was such a controversial book in its own way ... I'm just a bit blown away that they made a courageous decision," he told AAP.
Willacy received the award at a ceremony in Launceston on Tuesday.
His work exposing the unlawful killings was first aired on the ABC's Four Corners and led to a war crimes probe by the Australian Federal Police, and further investigations by the Brereton inquiry.
The veteran correspondent said the reporting had angered parts of the community, but said soldiers inside the SAS had helped him tell a story that Australia had to face up to.
Investigative journalism is expensive and time consuming, he said, but vital for digging up dark truths.
"It just shows how important it is for righting wrongs and trying to get to the bottom of the darker side of history," he said.
The prize for fiction went to Nicolas Rothwell for his novel Red Heaven, a coming-of-age novel about a boy set in Eastern Europe during the 1960s.
It's the third time the author has been recognised, having won the non-fiction category with Quicksilver in 2017, and being shortlisted for the 2014 fiction prize with Belomor.
Rothwell's win may spark further controversy for the awards, after the Australian Book Review complained in its December issue that the judging panels were heavy with people associated with The Australian, a newspaper the author has also written for.
But writer Geoffrey Lehmann, who oversaw the fiction and poetry judging, rejected allegations the judges lacked independence.
"Absolutely not, I would regard this as absolutely absurd," he told AAP.
He said the judges have diverse professional backgrounds and are selected from around the country.
"The idea that we are in some way biased towards either one geographical area or one particular way of looking at things, I find doesn't stand up," he said.
The 2022 judges were appointed by the previous government, a spokesperson for the Department of Communications said when asked for a statement regarding the integrity and independence of the panel.
"Each year the judges and the composition of the panels are reviewed," they said.
"Diversity, in all ways including across geographic location, gender, expertise and differing backgrounds, will be considered by the current government for the appointment of the 2023 Awards' judges."
With the prime minister and arts minister unable to attend Tuesday's ceremony, the awards were presented by the federal government's special envoy for the arts, Susan Templeman.
The winners were selected from 545 entrants and the total prize money for the awards is $600,000.
PRIME MINISTER'S LITERARY AWARD WINNERS:
* Fiction - Red Heaven by Nicolas Rothwell
* Non-fiction - Rogue Forces: An explosive insiders' account of Australian SAS war crimes in Afghanistan by Mark Willacy
* Poetry - Human Looking by Andy Jackson
* Australian history - Semut: The untold story of a secret Australian operation in WWII Borneo by Christine Helliwell
* Children's literature - Mina and the Whole Wide World by Sherryl Clark, illustrated by Briony Stewart
* Young adult literature - The Gaps by Leanne Hall
