Sri Lanka Week has shrunk to a long weekend. The trade and investment shindig in Melbourne’s Docklands was scheduled to take place in June, but was called off amid outrage over the Sri Lankan army’s pounding of Tamil areas and UN estimates of 20,000 deaths. It’s back on, from Friday to Sunday, promising visitors “the opportunity to feel and experience the taste of paradise”.

Instead, we should remember 300,000 inmates who are being held against their will in a living hell — the giant internment camp at Menik Farm — in violation of their rights under international and Sri Lankan law. Alarming eyewitness testimony trickles out, of food and clean drinking water in desperately short supply, filthy conditions and — for any who might be tempted to protest to the occasional foreign visitor — the ever-present threat of disappearance.

That’s a fate that has befallen thousands over the years, in Sri Lanka’s dirty war with the Tamil Tiger rebels, which ended just over five months ago. Various commissions of inquiry were set up, only to fail in bringing any of the culprits to justice: a “sham”, in the words of Amnesty International. So the bullies carry on with impunity, and impunity incentivises repetition: we got away with it once, why not do it again?

The menace spreads, potentially, far beyond the shores of this small island. Sri Lanka hijacked a meeting of the UN Human Rights Council and managed to get a resolution passed, congratulating itself for its “victory”. How many other governments are watching, making the calculation that they, too, can wade in to quell a non-state armed group, regardless of how many civilians they slaughter, and get off with little more than hand-wringing from the international community?

Now, though, the US State Department has issued an authoritative report, marshalling evidence of war crimes in the final desperate months of hostilities. It’s restrained in its language, and also even-handed. It identifies several occasions when the Tigers took boys as young as 12 to be soldiers, and intercepted civilians fleeing from danger to use them as human shields. But it lists credible reports from multiple sources that the army — or government-linked paramilitaries — attacked the so-called no-fire zone with heavy weapons; opened fire on medical facilities; killed senior Tiger leaders after they had agreed to surrender, and abducted and killed large numbers of Tamil men and boys.

“IDP checkpoints and camps were alleged to be particularly vulnerable areas”, it says, “with a heavy military presence hindering the ability of international organisations to conduct protection monitoring and confidential IDP interviews”.

This last point is particularly important. Sri Lanka’s High Commissioner and supporters of his government in Australia are holding a meeting in Canberra this week to brief our representatives and their officials. This will include a presentation on conditions in the camps, from a visit undertaken by a former newspaper editor, Mahindapala Don, who is now settled here. I have no reason to doubt Don’s sincerity in relating what he saw, but he did admit, in response to my email, that the trip was conducted by the military. It meets none of the conditions of professional humanitarian and human rights reporting, therefore, cannot be regarded as reliable.

MPs are likely to hear protestations that have become familiar to all of us who’ve spoken out about the Tamils’ plight. Respected monitoring groups such as Human Rights Watch and Amnesty are spreading “adverse propaganda”. The UN High Commissioner for Human Rights got it all wrong. The UK’s Channel Four News screened secretly recorded pictures appearing to show Tamil detainees being shot by troops in cold blood, then a later video revealing the appalling camp conditions — so its journalists must have been hoaxed.

Whether they will have the gall to claim the State Department, too, has had the wool pulled over its eyes, remains to be seen, but anyone who is prepared to appeal to Australians to go on holiday to Sri Lanka, given all that’s happened, must have a pretty thick hide. They are, in other words, in denial. The picture is further clouded by Sri Lanka’s dismal record on press freedom — 165th out of 173 countries, according to Reporters Without Borders. Journalists and NGO workers alike have been effectively intimidated by years of arbitrary arrests, harassment and regular unsolved murders among their ranks. When Australian James Elder, the head of UNICEF, spoke out about his concerns over malnutrition in the camps, he was promptly expelled.

The attempt to divert our legislators from focusing on the real human rights issues in Sri Lanka comes as the trial of Radovan Karadzic finally gets under way in the Hague. If he can be arraigned for taking command responsibility for the massacre at Srebrenica, then someone, somewhere, must surely be held accountable for the systematic bombardment of civilian areas documented in the report. Between January and May of this year, it lists at least 158 separate attacks that can only have come from the army side. The vast majority are incidents of indiscriminate shelling, with the occasional use of cluster bombs. And, it cautions, these are just the ones reported to the outside world: there are likely to have been many more.

At one point, the report notes, Sri Lankan Foreign Secretary Palitha Kohona admitted to Al Jazeera television that government forces had indeed shelled the no-fire zone, despite earlier official denials. The admission came after the station showed satellite imagery with analysis that documented shelling and air bombing damage within the zone between February 15 and April 19. Kohona maintained that this occurred before any civilians had actually entered the safe areas, but Al Jazeera then showed footage from an earlier interview with Kohona and with military spokesman Udaya Nanayakkara, which aired on April 19, the same day the satellite images were taken. In this, the pair insisted that the government was not shelling these areas due to civilian presence in them — a position “inconsistent with the claim that the shelling occurred before civilians entered these areas”.

The rules that say civilians should be protected in warfare are laid down in the Geneva Conventions. Recently, Australian Foreign Minister Stephen Smith and Attorney-General Robert McClelland welcomed the introduction of a new Additional Protocol to the Conventions, providing for a new internationally recognised symbol for humanitarian workers — the “Red Crystal” to go with the Red Cross and Red Crescent.

It was a welcome sign of the government’s commitment to the principles of Geneva, but they are at stake in Sri Lanka today, along with those of the Universal Declaration of Human Rights, which provides for people’s freedom of movement and entitlement to live in dignity. Up to now, there have been a few words of “concern” from Canberra, but no follow-through. The impression has often been given that Australia places greater emphasis on its trading relations and is reluctant to take any action to jeopardise them.

Next month, Kevin Rudd is off to the Caribbean, for a Commonwealth Heads of Government meeting in Trinidad and Tobago. At that occasion, the government of Sri Lanka must be held to account for its serious abuses of human rights and humanitarian law. It will be a very public opportunity for Australia to display some belated leadership by insisting that improvements be made in short order, or consequences will follow.

Jake Lynch is the director of the Centre for Peace and Conflict Studies (CPACS) at the University of Sydney.