The ethics for adding ancient works to American art museum collections became substantially more stringent five years ago when the Assn. of Art Museum Directors (AAMD) decided to set the bar higher -- prompted by complaints from Italy, Greece and other ancient lands that museums had long turned a blind eye to evidence that pieces they owned had been looted from archaeological sites.

On Wednesday, the AAMD, which has 217 member museums in North America, announced a few more subtle tweaks to those guidelines, including requiring a public explanation on the AAMD's website if a museum decides to acquire a piece despite gaps in its ownership record going back to the fall of 1970.

Under the landmark 2008 guidelines, the AAMD set up an Object Registry on its website where member institutions are expected to post pictures and information about newly acquired antiquities whose ownership record since 1970 is not clear and complete. The aim is to allow nations of origin or others with possible claims or information to learn of a work's whereabouts and come forward with new evidence.

The revisions adopted this week during the AAMD's mid-winter meeting in Kansas City, Mo., were proposed by a 15-member Task Force on Archaeological Material and Ancient Art chaired by Maxwell Anderson, director of the Dallas Museum of Art.

Going forward, museums that acquire ancient art despite a less-than-ironclad ownership record since 1970 will be required to explain the specific grounds for their decision, posting the details on the Object Registry.

Previously, they'd been required to use the registry to publish what's known about such works' past ownership, but not to also explain why they believed acquiring them complied with AAMD guidelines. 

The museum directors' group acknowledges that “even after the most extensive research, many works will lack a complete documented ownership history” -- so it allows its members to go ahead and acquire them based on "informed and defensible judgments." Now the public will have a window on their thinking.

The revised guidelines also give more specific and detailed examples of the kinds of information museums should gather and weigh while deciding whether to acquire antiquities that have gaps in their post-1970 ownership record.

Also addressed is a question not covered in the previous guidelines: what to do about antiquities that had been promised to a museum as gifts before 2008, but not yet conveyed to it. The revision says it's OK for a museum to accept such gifts if it decides that's the right thing to do -- but that the donated work must be posted on the Object Registry.

In the legitimate antiquities market, Nov. 17, 1970, has become a standard dividing line -- the date when the United Nations Educational, Scientific and Cultural Organization adopted a convention aimed at stemming the global trade in looted art and artifacts.

Until 2008, the more relaxed AAMD guidelines had said it was OK for museums to acquire ancient artworks whose whereabouts had been established going back only 10 years.

The guidelines also say that museums are expected to volunteer new evidence they uncover if it "establishes another party's right to ownership," and to repatriate the work "if the case warrants."

Sixteen museums – none of them in Southern California – currently have antiquities posted on the Object Registry, led by the Walters Art Museum in Baltimore, with 358, and the Iris & B. Gerald Cantor Center for Visual Arts at Stanford University, with 66. To put more teeth into the mandate to post works on the registry, that requirement has now been made part of the AAMD's separate code of ethics for museum directors.

The Getty Museum in Los Angeles has been hit hard by the movement to repatriate looted antiquities, with nearly 50 objects returned to Italy and Greece since 2007.

Last summer the Getty, which exhibits its ancient art at the Getty Villa in Pacific Palisades, began an internal effort to determine the ownership history of everything in its 45,000-piece antiquities collection and publish the results.

The AAMD's codes and guidelines are not legally enforceable, but the organization can ostracize member museums that violate them.

In 2008 it imposed a ban on members' cooperating with the National Academy Museum and School -- including loaning works for exhibitions -- after the New York City institution had sold two of its prized paintings to cover general operating expenses. The sanctions lasted nearly two years and were lifted in recognition of subsequent changes at the Academy.

The AAMD and another prominent organization, the American Alliance of Museums, say it's OK to sell collection pieces only if the money is funneled directly back into the collection, typically through other acquisitions. The AAMD did make at least one prominent exception for L.A.'s Hammer Museum.

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