BANGKOK — For decades Douglas A. J. Latchford, an 81-year-old British art collector, has built a reputation as one of the world’s great experts in Khmer antiquities, one whose generous return of treasures to Cambodia garnered him knighthood there in 2008. 
But last month Mr. Latchford, who lives here in an apartment brimming with Asian artifacts, was depicted less chivalrously in a civil complaint filed by the United States attorney’s office in Manhattan.
The federal lawyers said Mr. Latchford, identified in court papers only as “the Collector,” bought a 10th-century Khmer warrior statue in the early 1970s knowing that it had been looted from a jungle temple during the Cambodian civil war.
The lawyers are trying to help Cambodia recover the artwork, a 500-pound sandstone statue, which Sotheby’s in New York still hopes to sell for millions of dollars on behalf of its current owner.
For Sotheby’s and the federal government the court case is the latest pitched battle over what is fair and appropriate when regulating the sale of global antiquities.