A remarkable 72 hours in Port Moresby has seen an arrest warrant issued for Prime Minister Peter O'Neill, the Attorney-General and Deputy Police Commissioner sacked, and PNG's anti-corruption agency, Taskforce Sweep, disbanded. Respect for the rule of law and good governance from the highest political office in the land appears to be in meltdown.

The arrest warrant was issued based on information collected by Taskforce Sweep and PNG police and relates to the long-running scandal over fraudulent payments from the PNG Finance Department to Paraka Lawyers. New evidence suggests O'Neill, as finance minister, personally signed off on many of these payments. O'Neill sought a court injunction against the arrest warrant and announced he would establish a separate Commission of Inquiry into the corruption allegations. The court has not yet granted a stay of the warrant and after two sittings has now adjourned further consideration until 25 June.

O'Neill sacked his Attorney General, the well regarded Kerenga Kua, on the evening of 17 June, claiming he threatened the integrity of the government when he opposed proposed amendments to the constitution. These amendments would have further entrenched the power of the ruling party.

Yesterday O'Neill took the further extraordinary step of disbanding Taskforce Sweep, putting its head, the courageous Sam Koim, out of a job. O'Neill created Taskforce Sweep and said on numerous occasions that he fully supported its corruption investigations against politicians. But his support was only ever going to last as long as the Taskforce did not come knocking on the Prime Minister's door.

PNG's police are also caught up in the turmoil. Police Commissioner Tom Kulunga exited the scene after he was convicted of contempt of court last week, but the O'Neill-appointed replacement, Geoffrey Vaki, did not have the confidence of the force. When Deputy Police Commissioner Simon Kauba moved against him, Kauba too was sacked by O'Neill. The plot thickened still further last night, with Vaki charged with perverting the course of justice and released on bail.

O'Neill is unlikely to gain the respect of the people with what is looking more and more like a desperate bid to avoid any investigation into his past actions and hold on to power, and PNG's young educated class are expressing frustration and anger via social media.

But having the respect of the people matters little as long as the Prime Minister has the numbers on the floor of the parliament, and despite his sacking of competent, high profile ministers like Kua (and earlier, former Treasurer Don Polye), O'Neill still commands a large majority in parliament. PNG's major foreign investors will be worried about what these incidents reveal about the Prime Minister's character. But as he is the chief decision-maker where their interests are concerned, they are unlikely to protest.

The chaos of this week presents a difficult challenge for the Australian Government, which has a close relationship with Peter O'Neill. The previous Labor government developed close ties with O'Neill from the time he became prime minister in August 2011, welcoming him on a visit to Canberra soon afterwards. Both Prime Minister Gillard and Foreign Minister Rudd avoided saying too much about PNG's constitutional crisis, which saw Prime Minister O'Neill and his predecessor Sir Michael Somare both claiming rights to the top job. This enabled Canberra to maintain its friendship with O'Neill but left the clear impression that Australia was not concerned that the Prime Minister had put self-protection (in the name of stability) ahead of respect for both the constitution and the Supreme Court. Kevin Rudd's asylum-seeker deal with Peter O'Neill in July last year further entrenched Canberra's ties with the PM.

While Julie Bishop likely has a good appreciation of O'Neill's faults, she has worked hard to enhance Australia's political relationship with PNG and that means a good relationship with O'Neill. Now she must walk that fine line between demonstrating Australian support for transparency, accountability and the rule of law in PNG and avoiding making an enemy of Peter O'Neill, who is still critical to the success of a number of Australian policies, not least on asylum seekers.

Foreign Minister Julie Bishop told the ANU's State of the Pacific conference yesterday:

To underpin economic growth in the Pacific, we need strong political and community leadership, with sound institutions and respect for the rule of law. It is vital for there to be transparency and accountability, strong anti-corruption regimes and robust police and defence forces. The Pacific, with its unique challenges, opportunities and constraints needs vision and leadership from within.

When asked at the National Press Club a few hours later about the crisis and Australia's aid to PNG, Ms Bishop said PNG was family for Australia and our close friendship meant Australia would continue to support PNG. She described the events of the last few days as an internal matter for the PNG Government. Bishop may have sent a subtle signal to O'Neill with her remark about the need for strong anti-corruption regimes but he undoubtedly knows there is little risk Canberra will hold him to account for his actions of this week.

While Peter O'Neill's preference for holding on to power predictably won over his commitment to tackling endemic corruption in PNG, it is encouraging that there are opposing voices. Taskforce Sweep's Sam Koim is undeterred from his ambition to rid the country of corruption. He would be under considerable personal risk but his courage in speaking out deserves support.