“It is not a healthy place,” Professor Rimmer said. “It runs on alcohol and gossip and fumes and power.”
Mr. Joyce, a gregarious bull of a man often seen in a trademark Akubra bush hat, now faces a series of uncomfortable questions:
• Were public funds used to cultivate an extramarital affair?
• How did he and his new partner, Vikki Campion, a former journalist, end up in a supporter’s free apartment?
• How did Ms. Campion secure a high-paying job with a Parliament colleague?
• And, did Mr. Joyce grope a woman after an awards ceremony in 2011?
Mr. Joyce, 50, has denied groping and other ministerial misconduct. He has spent much of the week offering defiance and remorse, and trying to hold on to his job.
He acknowledged his relationship with Ms. Campion on Tuesday, apologizing to his family, his constituents and the National Party of Australia, which he still leads.
But he also told his party colleagues he would not step down. “Every political career has a time of trial,” he said.
His stand fits with his longstanding “just a bloke” appeal. He grew up on a farm in Tamworth, in Australia’s southeast, which is home of the nation’s largest country music festival. Mr. Joyce is known as an off-the-cuff maverick who is loyal less to ideology than to his constituents.
But since 2004, he has been a Canberra man. He was a senator for Queensland and then joined the House of Representatives in 2013. He became leader of the National Party and deputy prime minister in 2016.
Mr. Joyce is no stranger to scandal. A few years ago he made headlines worldwide when he threatened to euthanize two dogs belonging to Johnny Depp and Amber Heard after the celebrity couple brought them to Australia without the proper documentation and quarantine.
Last year, Mr. Joyce was one of several politicians revealed as holding dual citizenship.
After the High Court ruled that he had been ineligible to run for Parliament because of it, Mr. Joyce renounced his New Zealand citizenship and returned to his district to campaign again for his seat. He won comfortably.
But experts say the backlash has only been intensified by his supposed authenticity, his eagerness to parade his wife and four children in political campaigns, and his brash conservative positions, like his opposition to same-sex marriage, which he argued it would destroy families.
“The public expected a Barnaby that was a solid country family man, and we’re seeing that he’s not that at all,” said Jill Sheppard, a lecturer in politics at the Australian National University in Canberra.
“If there was a political trait Australians hate, it’s hypocrisy,” Professor Rimmer said.
But the biggest threat to Mr. Joyce’s career may involve questions about the mingling of adultery, money and power.
Records show he claimed a travel allowance for 50 nights in Canberra last year when Parliament was not in session, far more than other senior leaders.
Government watchdogs and journalists have also zeroed in on two high-paying positions that were allegedly created for Ms. Campion in the offices of a party colleague, Senator Matt Canavan.
Mr. Joyce and Prime Minister Turnbull — who has continued to back him — said the jobs were beyond reproach because Ms. Campion was not technically his partner at the time.
Mr. Joyce’s critics contest that assertion.
Officially, for now, Mr. Joyce still has the support of his party. “Barnaby Joyce is the best deliverer for rural and regional Australians in generations,” Bridget McKenzie, the Nationals deputy, told reporters on Wednesday.
But time is not on his side. Mr. Turnbull is scheduled for an overseas trip that includes meeting with President Trump on Feb. 23, which would make Mr. Joyce the acting prime minister.
A broader reckoning on the capital’s workplace culture may also be coming.
“If the Australian public feels the political class is isolated and don’t appreciate their concerns, then that’s a problem the political class has to respond to,” said Andrew Giles, a Labour Party politician.
“We’re not meeting people’s expectations,” he added. “And they’re legitimate expectations.”