Sri Lanka's civil war was one of the most bloody internal conflicts in history. Fought between the Sri Lankan state and the separatist militia known as the "Liberation Tigers of Tamil Eelam" (LTTE), the internecine struggle is estimated have led to 100,000 deaths since its outbreak in 1983.

In early 2009, as the war neared its conclusion, hell on earth was very likely unleashed on civilians assembled in the confines of a so-called "no fire zone" on the north-eastern coast of Sri Lanka in a region known as the Vanni, according to human rights groups and a report produced by a United Nations panel last year.

It is estimated that up to 40,000 civilians, predominantly from Sri Lanka's ethnic minority Tamil community were killed by "widespread shelling and the denial of humanitarian assistance", among other alleged acts of criminal, egregious cruelty committed by the Sri Lankan armed forces. The LTTE, whose leadership were mostly killed or captured by the Sri Lankan army at the end of the war, are also believed to have engaged in atrocities that would amount to serious war crimes.

Only last week, Channel Four aired a documentary entitled "Sri Lanka's Killing Fields: War Crimes Unpunished" that appeared to contribute to an already compelling body of evidence that suggests that key figures in the political and military elite of the island nation knowingly oversaw such abuses. It also appeared to display devastating evidence of extra-judicial killings (including the execution of a child)- a war crime according to international law.

At present, Geneva plays host the 19th session of the United Nations Human Rights Council, where the international body is set to vote this week on a resolution censuring Sri Lanka for its failure to demonstrate robust accountability for its wartime conduct. It is some matter of acute embarrassment for the Council, but it bears mentioning that in its previous resolution on the issue, the UNHRC passed a motion congratulating President Rajapaksa and his administration for their victory over the LTTE, while paying little attention to the serious allegations levelled at Colombo.

Things look very different now. It has been over a thousand days since the conclusion of the civil war. After achieving victory, Sri Lanka's President Mahinda Rajapaksa reassured the UN Secretary General that an internal inquiry headed by a panel known as the "Lessons Learnt and Reconciliation Commission" (LLRC) would deal comprehensively with all allegations of abuses by his forces. Last year, the LLRC report was released - already bedevilled by claims that the panel suffered from multiple conflict of interest issues- to heavy criticism from human rights agencies. According to such groups, the report totally failed to rigorously address the most serious accusations against Colombo.

Since the opening of the session in Geneva, Sri Lanka have been lobbying hard to influence the vote, which could leave open the option for Colombo to be subjected to an independent probe under the auspices of the UN. There have many complaints of attempted intimidation by the enormous governmental delegation against those with whom they disagree. Human Rights Watch director, Kenneth Roth tweeted earlier in the month: "UN Human Rights Council president chastises #SriLanka (w/o naming it), for videoing, harassing and intimidating NGOs criticising [the country]"

Such reported misbehaviour in Geneva will do little to efface Colombo's reputation as a major human rights offender, nor does the worrying abduction in Colombo last month of the complainant in a court case against the police, just days before his allegations of torture at their hands was due to be heard by a judge.

The man, who is still missing, like many others before him is believed to have fallen victim to the "white van" phenomenon- a serious ongoing human rights problem in Sri Lanka. Many journalists critical of the government or other forms of institutional power are reported to have been murdered or conveniently abducted by these vehicles.

Mangala Samaweera, Sri Lanka's former foreign minister told the Daily Telegraph in 2009 that "it is an open secret that extra judicial death squads have been operating with impunity since 2006" in Sri Lanka. One of these death squads who use the vans, he explains, are "known as 'Gota's sinha mafia", a reference to Gotabaya Rajapaksa, the Defence Secretary. A former general from the Lankan armed forces has made a parallel claim under testimony in the US that corroborates the former minister's assertions regarding the alleged "death squads". The source claimed that a "Colombo Security" figure connected to the police oversaw the white van assassinations while "directly getting orders from the secretary."

That Sri Lanka has a human rights problem is hardly in doubt. That Sri Lanka has so far failed to convincingly deal with the ghosts of its past is also difficult to contest. The mounting, credible evidence that sickening atrocities against tens of thousands of civilians occurred during the war should make the vote in Geneva a no-brainer to those who value human rights, governmental accountability and international law.

Unfortunately, in the world of realpolitik and international relations this is not always the way that things play out.

Whether Sri Lanka's tortured past can be left to drift into an Orwellian memory hole or be held up to scrutiny is now up to the Human Rights Council: let us hope that each member will decide to vote according their conscience.

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