On September 4, Judge Naomi Buchwald of the Southern District of New York dismissed an Alien Tort Statute suit against President Mahinda Rajapaksa of Sri  Lanka, on the basis of a Suggestion of Immunity filed by the Justice  Department, at the request of the State Department Legal Adviser.  Under  customary international law and longstanding U.S. practice, sitting  heads of state or government are considered to have immunity from civil  suits in U.S. courts.
This is the second human rights suit against President Rajapaksa to  be dismissed this year based on a U.S. Suggestion of Immunity.  As I  explained here,  in February, Judge Kollar-Kotelly of the U.S. District Court for the  District of Columbia dismissed a TVPA suit against Rajapaksa, based on a  virtually identical Justice Department request.
The Justice and State Departments seem to have acted much more quickly in responding to the request of the Government of Sri Lanka for a Suggestion of Immunity in this case. The suit was filed in September 2011 by the widow of an LTTE member who was allegedly captured and then killed by Sri Lankan armed forces; the Justice Department filed its Suggestion of Immunity on April 26, apparently without being asked by the Court.
Judge Buchwald’s decision is also notable for her rejection of the  plaintiff’s argument that head of state immunity should not shield  officials accused of jus cogens violations.   Many human rights lawyers,  who are understandably uncomfortable that customary international law  principles of immunity are in tension with efforts to hold  senior  government officials accountable for human rights violations, have urged  that immunity principles should not apply to serious violations of  human rights.  But Judge Buchwald said: “Here, plaintiff and Amicus seek  to impose civil liability on a sitting head of state in a domestic  forum, a proposition that has been soundly rejected by U.S. courts, even  in the context of alleged jus cogens violations.”
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