The treasure's future and its potential art market value seem equally uncertain, since it seems inconceivable that any of the few museums that could afford the hoard would contemplate buying it without knowing the truth about its discovery and subsequent history - none of which emerged in court.
The undisputed facts relating to the discovery are few. The treasure consists of 14 pieces of the highest standard of late Roman craftsmanship, spectacular silver plates, buckets, basins and ewers with raised and engraved decoration, and bearing the name 'Sevso' - presumed to have been a high- ranking Roman military officer serving somewhere in the far-flung Roman empire.
Only one other fact seems certain. This is that it was bought by the Marquess of Northampton a decade ago, with a view to eventual re-sale through the agency of the late Peter Wilson, a former (and controversial) chairman of Sotheby's. Mr Wilson's immediate source was claimed to be an agent acting for an unidentified Lebanese owner, and the silver was reportedly accompanied by a Lebanese export certificate, subsequently denounced by the government of Lebanon as a fake.
Lord Northampton appears to have been seriously misled on at least two points: that the discovery and export of the items had been entirely above board, and that it would be easy to sell the treasure at a profit, presumably to a major museum. It seems very possible that the New York jury felt unwilling in effect to punish Lord Northampton, who is seen as an innocent victim in the dispute.
If the Sevso silver was really found together inside a copper container sometime in the Seventies, where did it come from? The collection is greatly devalued in archaeological (and probably financial) terms without this essential provenance. Whatever the answer, it will re-open the international disputes about its ownership.
Virtually every square mile covered by the third- and fourth-century AD Roman empire, whether in Europe, Asia or Africa, has for at least two decades been subject to national archaeological protection and/or export regulations. Almost all the nearly 40 countries within the former empire have strict laws requiring the prompt declaration of all such archaeological finds, and all regulate their export. Although the law in England and Wales is among the weakest, such a find would have to be reported promptly to the coroner as possible treasure trove, and an export licence would be required.
Consequently, if the Sevso Treasure has been excavated in recent times, as claimed, it does not matter where in the former Roman world it was found: either its clandestine excavation or its removal from its country of origin, (probably both) was illegal. In the case of one of the frequently rumoured find spots, the Syrian-influenced part of eastern Lebanon, international war crimes law may also come into play. Both Lebanon and Syria are parties to the 1954 Hague Protocol of the Protection of Cultural Property in the Event of Armed Conflict, which in effect makes illegal all movements of items of cultural interest out of any international or civil war zone or area of occupation.
There is a very large question mark over what happens next. The Sevso material is of 'museum' quality, and Mr Wilson and Lord Northampton anticipated that most major international museums would be competing with each other to acquire the collection - hence the extraordinary pre-auction estimates that were bandied about.
However, virtually every major museum in the world, and more than 8,500 individual directors, curators and other museum professionals, have voluntarily bound themselves to work only within the International Code of Professional Ethics of the International Council of Museums, and most have their own internal ethical and acquisition codes. With acquisitions of this kind the obligation of the museum's governing body and staff under the code is not merely: 'Has anyone proved that the material is stolen or smuggled?' On the contrary, museums must satisfy themselves that the evidence of the provenance and history of the material prove that the vendor has a good legal title, the material does not come from an illegal, clandestine or unscientific archaeological excavation, and it has not been exported, imported or otherwise transferred from its country of origin or any intermediate state in contravention of any applicable national or international antiquities protection or export control law.
However, revealing the truth about the Sevso Treasure's origin would almost inevitably result in further legal action by the declared country of origin. Further, as the United States has now enacted as national law the 1970 Unesco international convention on illicit trafficking, the US government itself would be obliged to give all appropriate assistance to the country of origin in taking legal action to recover the collection.
Quite apart from any ethical considerations, the few potential buyers of the silver must realise that there is more to be known about the Sevso Treasure than has so far become public. It seems unthinkable that those with ultimate legal responsibility for the financial assets of museums would be prepared to risk millions of trust funds buying not just the Sevso Treasure, but a ticking time-bomb in the form of possible unwelcome revelations, such as proof of illicit excavation and smuggled export. Most private collectors are going to be just as cautious.
If any are tempted for a moment, the sight of New York's Metropolitan Museum emptying its showcases and strongroom of the so-called Lyrian Hoard of gold in readiness for its return to Turkey after more than a decade of drip by drip damaging revelations about the legality of its excavation and export to the Metropolitan should be enough to stiffen their ethical resolve.
The author is Vice-President of the International Council of of Museums and chaired the committee which drew up its International Code of Professional Ethics.
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