The Getty Center in Los Angeles, the Metropolitan Museum in New York and Sotheby's auction house — these are just some of the major institutions that have been forced to repatriate artworks in recent years. Italy, Egypt, Greece, Turkey and Cambodia have all successfully used their cultural property laws to secure the return of important antiquities from collectors and museums.
Treasures from King Tutankhamen's tomb that had been in the Met's collection for almost a century went back to Egypt. In 2006, the Met agreed to return the Euphronios krater, a masterpiece Greek urn that had been a museum draw since 1972. In 2007, the Getty agreed to return 40 objects to Italy, including a marble Aphrodite, in the midst of looting scandals. And in December, Sotheby's and a private owner agreed to return an ancient Khmer statue of a warrior, pulled from auction two years before, to Cambodia.
Cultural property, or patrimony, laws limit the transfer of cultural property outside the source country's territory, including outright export prohibitions and national ownership laws. Most art historians, archaeologists, museum officials and policymakers portray cultural property laws in general as invaluable tools for counteracting the ugly legacy of Western cultural imperialism.
During the late 19th and early 20th century — an era former Met director Thomas Hoving called "the age of piracy" — American and European art museums acquired antiquities by hook or by crook, from grave robbers or souvenir collectors, bounty from digs and ancient sites in impoverished but art-rich source countries. Patrimony laws were intended to protect future archaeological discoveries against Western imperialist designs.
But as it turns out, those laws may not be an unalloyed good. In country after country, empirical data show that when rigid cultural property laws are put in place, major archaeological excavations and discoveries slow markedly, making source countries — and the world at large — culturally poorer.
I surveyed 90 countries with one or more archaeological sites on UNESCO's World Heritage Site list, and my study shows that in most cases the number of discovered sites diminishes sharply after a country passes a cultural property law. There are 222 archaeological sites listed for those 90 countries. When you look into the history of the sites, you see that all but 21 were discovered before the passage of cultural property laws.
On average in art-rich countries, discoveries that landed on UNESCO's list diminished by 90% after these laws were passed. To illustrate: Italy has seven archaeological sites on the World Heritage list; five were discovered before its 1909 cultural property law, but only two after.
Many variables may cause a drop-off in archaeological discoveries country by country, but statistically speaking, it's nearly impossible that the decline shown in the data isn't also related to the passage of cultural property laws.
Strict cultural patrimony laws are popular in most countries. But the downside may be that they reduce incentives for foreign governments, nongovernmental organizations and educational institutions to invest in overseas exploration because their efforts will not necessarily be rewarded by opportunities to hold, display and study what is uncovered. To the extent that source countries can fund their own archaeological projects, artifacts and sites may still be discovered. But the drop in World Heritage Site discoveries after passage of cultural property laws suggests that external sources aren't as active as they were and domestic funding isn't offsetting the loss.
The survey has far-reaching implications. It suggests that source countries, particularly in the developing world, should narrow their cultural property laws so that they can reap the benefits of new archaeological discoveries, which typically increase tourism and enhance cultural pride. This does not mean these nations should abolish restrictions on foreign excavation and foreign claims to artifacts.
China provides an interesting alternative approach for source nations eager for foreign archaeological investment. From 1935 to 2003, China had a restrictive cultural property law that prohibited foreign ownership of Chinese cultural artifacts. In those years, China's most significant archaeological discovery occurred by chance, in 1974, when peasant farmers accidentally uncovered ranks of buried terra cotta warriors, which are part of Emperor Qin's spectacular tomb system.
In 2003, the Chinese government switched course, dropping its cultural property law and embracing collaborative international archaeological research. Since then, China has nominated 11 archaeological sites for inclusion in the World Heritage Site list, including eight in 2013, the most ever for China.
China's recent legal and archaeological development provides powerful evidence that changes in cultural property laws can alter incentives and increase culturally important discoveries. In light of the data, source nations — and UNESCO, whose 1970 anti-looting treaty plays an outsized role in these laws — should consider legal reforms to reverse the dramatic decline in archaeological discoveries that began with the spread of restrictive cultural property laws.
Attorney Adam Wallwork's study of patrimony laws was published in the Indonesian Journal of International and Comparative Law in January.