Sri Lanka`s Killing Fields: War Crimes Unpunished is a follow-up to a film aired last June by Channel 4, and this one, too, is full of images of graphic violence and suffering, including what appears to be the body of a 12-year-old boy, the son of former Tamil Tiger leader Prabhakaran, shot five times in the chest at close range. International-law experts interviewed in the documentary called it a crime and a war crime.

That allegation is one of four case studies presented in detail the others include allegations that the Sri Lankan government knowingly shelled a U.N. field hospital, denied adequate food and medicine to civilians in a so-called no-fire zone and fired heavy weapons into an area full of civilians, whom it then claimed to have rescued in a humanitarian operation. The Sri Lankan government has categorically denied all the allegations in the latest Channel 4 report:

The timing is certainly not coincidental. The UNHRC resolution is only the latest effort to call the Sri Lankan government to account for its conduct during the final phase of the war. The Channel 4 documentary presents some of the most shocking allegations of atrocities, but they are by no means the first. During the last few months of the war, there were numerous reports of civilian casualties and forced detention of civilians. But unlike the conflict in Syria, there were no independent observers in the war zone in the war against the Tamil Tigers the Sri Lankan government refused to allow journalists or international aid agencies to document what was happening so the calls for accountability began only after the fighting had ended. In October 2009, U.S. officials interviewed Defense Secretary Gotabaya Rajapaksa, the President`s brother, who is a U.S. citizen, and former army chief Sarath Fonseka, who is a green-card holder. In 2010, the U.S. State Department`s point man on war crimes, Stephen Rapp, looked into the issue. Last year, the U.S. spent most of its diplomatic energy pushing the Sri Lankan government to launch a credible investigation of its own, through its Lessons Learnt and Reconciliation Commission

The LLRC was a disappointment. While it did acknowledge, for the first time, that there were significant civilian casualties, the report, nonetheless, does not fully address all the allegations of serious human-rights violations that occurred in the final phase of the conflict, State Department spokeswoman Victoria Nuland said shortly after it was released in December 2011. The State Department then called on the government of Sri Lanka to show that it was serious about accountability. The new resolution before the UNHRC is a sign that the U.S. has concluded that it is not, and will now take the case against Sri Lanka to the international community.

Sri Lanka has been pushing hard to win the vote at the UNHRC and it seems confident of Indian support. In an interview with NDTV, the Sri Lankan Foreign Minister commented, India is our closes neighbor and friend and is a responsible world power. They will take the right decision at the right time. Even those in the Indian political establishment, like the retired diplomat and commentator M.K. Bhadrakumar, acknowledge that this small country has deftly outplayed India, the regional superpower.

If its resolution at the UNHRC passes, the U.S. will be left with few other options. It could try to prosecute Gotabaya Rajapaksa, a U.S. citizen it could push for sanctions or ask the U.N. Security Council to refer the case to the International Criminal Court. None of those seem very likely but in any case, the Sri Lankan government has already made some moves to protect itself. It has moved several top military officials, including two of those named in the Channel 4 report, into senior diplomatic posts, which give them immunity from prosecution.

In a sense, this month`s battle at the UNHRC is the yet another stage in a long endgame to the war against the Tamil Tigers, one that President Mahinda Rajapaksa and others in his government have been strategizing for years. In a July 2009 interview, I asked him about the possibility of action against him for human-rights abuses.

TIME: What if an elected government is acting against its own people?

Rajapaksa: Are you going to punish the whole citizens for that, or the man who is responsible? Anywhere in the world if something goes wrong, they punish the whole country. Take me. Say that I violated all these human-rights violations, killed people, right? Do you punish me, Mahinda Rajapaksa, or the innocent people of this country by sanctions, embargoes, travel advisories? You punish the whole country.

TIME: What is the appropriate punishment, then, for an elected government?

Rajapaksa: You can take him out of U.N. membership. But still give the facilities to the people. Or ban him [from travel by not] giving visas. There are ways of punishing me if you want. There, now by saying that, I will get punished.

Then he laughed.