As she stared down the barrel of an unprecedented two-week expulsion from NSW parliament on Tuesday, Penny Sharpe, leader of the minority Labor government in the upper house, asked plaintively: “At what point does this stop?”Two days later, her deputy, Transport Minister John Graham, was also booted from the Legislative Council.For months, Labor has been at loggerheads with opposition and crossbench MPs in the upper house.But what began as simmering resentment this week exploded into whole-scale rebellion with Labor increasingly losing its grip on an unruly Legislative Council as the two senior ministers were turfed out thanks to an unlikely alliance of MPs from the opposition Coalition, the Greens, and the independent Mark Latham.The background to the uprising depends on who you ask. Ask a Labor MP, and they will tell you it is about the Greens and the Coalition joining an “unholy alliance” with a vengeful Latham, who is leading them by the nose to pursue “conspiracy theories” against a first-term government.This week in parliament Premier Chris Minns accused the upper house Coalition of undermining Opposition Leader Kellie Sloane to support Latham, whom he called a “certified lunatic” and a “crazy person”, and Labor MPs have relentlessly attacked the Greens for siding with Latham following a finding that he had vilified independent MP Alex Greenwich in a series of homophobic messages on social media.Greens MPs, Graham said on Thursday, had failed to “lift a finger” to condemn Latham.Or, it is a fight about protecting the upper house’s transparency powers against an increasingly secretive and opaque Labor government that has already hobbled the upper house’s ability to compel witnesses to attend public inquiries — after a court challenge by Minns’ chief of staff, James Cullen — and is now seeking to further curtail its influence by refusing to comply with the parliament’s ability to force the production of secret documents. Greens MP Sue Higginson said the crossbench was being “gaslit” and wedged by the government.“We saw the Minns Labor government offend the powers to summons witnesses to our inquiries. Now we see the Minns Labor government trying to weaken the power of calling for papers,” she said. “It is clear and plain to anyone watching what is happening.”Either way, the functioning of parliament, and a host of bills the NSW Labor Party wants to pass before election season kicks off in earnest are at risk. So too are the powers of the council, which have helped uncover a string of scandals in NSW, including pork-barrelling under the Berejiklian government, John Barilaro’s trade commissioner imbroglio, and a national outrage over failings in the childcare sector.Labor MPs Courtney Houssos, Penny Sharpe, Daniel Mookhey and John Graham (left to right) listen to John Barilaro who was brought before the upper house when Labor was in Opposition. Upper House inquiries earned Mookhey a reputation as forensic inquisitor.