After months of build-up, and potent language suggesting she would not engage in horsetrading over humanity, independent senator Jacqui Lambie’s shock decision to back the repeal of the medevac laws is a betrayal that will haunt her politically. Citing unspecified national security concerns cuts no ice when the hundreds of asylum seekers in Papua New Guinea and Nauru present no threat to Australia. Lambie’s crocodile tears in the chamber this morning count for nothing compared with the needless suffering that will be inflicted on sick people who will be denied proper and timely medical treatment henceforth, to Australia’s shame. Condemnation of Lambie’s decision from Labor, the Greens and other crossbenchers has been swift and unequivocal. Doctors and refugee advocates who have, until now, taken Lambie at her word are dismayed. And open democracy in Australia takes another step backwards after unpopular legislation passes due to a secret deal between an authoritarian-leaning government and a personality politician. If Scott Morrison and Peter Dutton want to call that a win, they’re welcome to it.

In the Senate this morning, ahead of the crucial vote, there was speculation about a secret deal that had been done. Government leader Mathias Cormann denied that this was the case, a denial that was apparently contradicted when Lambie declared her intentions, saying: “I put a proposal to the government, and since then we have worked together really hard to advance that proposal. We’ve worked to an outcome I believe we both want, which is an outcome where our borders are secure, the boats have stopped and sick people aren’t dying while waiting for treatment. As a result of that work, I’m more than satisfied that the conditions are now in place to allow medevac to be repealed.” That certainly sounds like a deal, although Lambie did not use the word.

Greens Leader Richard Di Natale jumped up and put on the record that either Cormann or Lambie must be lying. Addressing Cormann directly, Di Natale said: “We’ve just heard that you and Senator Lambie have worked on a secret proposal, in good faith, that she cannot disclose for so-called national security reasons, and you, only a few moments ago, stood up and said there was no deal. In fact, you walked over to Senator Lambie and said, ‘Is it okay if I say there’s no deal?’ We heard you say it. Who’s lying? Who’s misleading this parliament?”

Later on in Senate Question Time, as Guardian Australia reported, Di Natale asked a more pointed question about whether there had been an exchange of letters with Lambie. Cormann did not rule it out, saying: “I won’t go into private conversations … What I can say is there has been no deal to change our stance on border protection or anything else. We provided briefings, we did not provide any undertakings to change policy … We provided detailed information about what the policies of the government are.”

The prime minister stuck to a similar script at a press conference this afternoon, saying he’d fulfilled a promise to the Australian people by repealing the medevac laws, and would not be drawn on the substance of any deal the Coalition had struck with Lambie. When pressed on whether that might include a resettlement option, potentially to New Zealand, Morrison chose his words carefully: “The government is always looking at ways to resettle those who are on Nauru.”

Perhaps there is a resettlement deal, which Lambie hinted during the past fortnight was her one condition for supporting the medevac repeal. The opacity is farcical. And if Australians are in the dark about what happened today, what are those hundreds of asylum seekers held in PNG and Nauru to make of it, and what it means for their future? Meanwhile, Sky News Australia has been told that the Ardern government has been informed that Iranian journalist Behrouz Boochani, detained for more than six years on Manus Island but who recently travelled to New Zealand, has applied for asylum there.

Refugee Action Coalition spokesperson Ian Rintoul today decried a “shocking campaign of orchestrated leaks, lies and misinformation in the government’s efforts to have the medevac bill repealed. The minister himself has directly approved 86 per cent of all medevac applications. There has never been a connection between people seeking asylum and national security … The government cannot escape its responsibility for those they are holding offshore. We expect the government to transfer all those approved by medevac and to continue processing the applications that have been made.”

This morning Lambie also voted against a Labor amendment that would have spared those people already in the medevac process. The prime minister was effusive in thanking her this afternoon, and sought once again to make political mileage out of cruel border protection policies. “I am pleased that [Senator Lambie] has enabled us to shut the door that Labor sought to prise open last year,” he said. “Thankfully the Australian people had their say on May 18, and they said ‘shut that door’, and we did that today on the basis of their endorsement at the last election.”