Sri Lanka’s president, Mahinda Rajapaksa, said Tuesday that his government would not cooperate with the United Nations investigation begun last month into suspected human rights abuses, including possible war crimes, committed during Sri Lanka’s civil war. Mr. Rajapaksa’s intransigence puts Sri Lanka in the company of North Korea and Syria, two countries that also barred access to United Nations human rights investigators.

Mr. Rajapaksa claims Sri Lanka can handle the inquiry on its own. This is doubtful. It was the Sri Lankan government’s failure over several years to prosecute and punish perpetrators of abuses during the civil war that prompted the United Nations Human Rights Council in March to request a comprehensive investigation.

Both the rebels of the Liberation Tigers of Tamil Eelam, or L.T.T.E., and the Sri Lankan military are thought to have committed war crimes. The United Nations estimates that 40,000 Tamils died during the final weeks of the conflict. Hundreds of thousands of people were interned in camps under military guard after the war ended in 2009. People suspected of being linked to the L.T.T.E. were tortured. Thousands simply disappeared.

The safety of witnesses is a major concern. People demanding accountability for those who disappeared have faced threats and arrest. Sri Lanka’s Prevention of Terrorism Act is being used to detain people without trial. After the United Nations high commissioner for human rights, Navi Pillay, visited Sri Lanka last year, she reported that she had never seen such a “level of uncontrollable grief” as that of families of the disappeared in Sri Lanka, and that people with whom she met were promptly visited by security forces.

Ms. Pillay has said that the United Nations investigation would go forward despite Mr. Rajapaksa’s denial of access. If Mr. Rajapaksa’s goal is truly, as he claims, truth, justice and reconciliation, he should cooperate with the investigation. Failing to do so will only feed international suspicions that his government has much to hide.

(The New York Times)