A legal innovation or an effort lacking enforcement?
Since the ancient times, cultural property (moveable and immoveable) has been increasingly subjected to destruction and plundering; a custom commonly associated with warfare.  By the 17th century, and more vividly in the late 19th - early 20th century, the international community eager to enforce protection accommodated the drafting of bilateral/multilateral/universal declarations, treaties etc., for the protection of cultural property. 
The unprecedented destruction and plundering of the WWII by the Nazis, proved the inefficacy of these attempts, whilst the effects of the WWII smuggling are still enduring.  Inevitably, the atrocities of WWII led to the creation of international/intergovernmental organisations like UNESCO  and the Council of Europe with the agenda to accommodate (among other matters) the safeguarding of cultural property/heritage through the enforcement of international instruments and intergovernmental actions/declarations. 
This article provides brief insights on the provisions of key international mechanisms that render the smuggling in art and antiquities a violation of international law. It is important to note that none of the conventions enacted has a retroactive effect (unless expressed otherwise in the instrument), as a general standard of international law. 
The 1954 Hague Convention
The 1954 Convention for the Protection of Cultural Property in the Event of Armed Conflict is the instrument that introduced internationally the concept of cultural property. The instrument renders the deliberate targeting of cultural property during military operations an infringement, unless the doctrine of military necessity can be successfully justified.  Further, the Convention imposes individual criminal responsibility, in line with ‘the experiences of the Military Tribunal of Nuremberg’ that followed the ceasefire of WWII. 
Protocol (I) of the Convention prohibits the exportation of protected cultural objects from any occupied area and imposes an obligation on a state that failed to prevent this to pay compensation to any good faith purchaser that purchased such kind of property.  This occurs upon the true owner’s successful claim of the object, whilst the instrument imposes no time limitations for raising such claims.  Regardless of its status as international customary law, the general perception over the Convention has been that it has failed its mission, empirically, because of the destruction and plundering that followed in Eastern Europe and Asia, in the late 20th century. 
The 1999 Protocol (II), in response to the inefficacy of the 1954 instruments, introduces higher thresholds, and creates criminal offences for ‘Serious Violations’ including ‘making […] cultural property the object of […] theft […]’ . The Protocol further requires the contracting parties to introduce criminal offences domestically, as well as impose sanctions in line ‘with principles of [domestic] […] and international law’.  It also requires them to ‘extend individual criminal responsibility to persons other than those who directly commit the act’.  The Protocol introduces grounds of ‘Other Violations’ in Article 21(b) , including 'any illicit export, other removal or transfer of ownership of cultural property from [the] occupied territory’, encouraging the contracting states to adopt the measures they deem appropriate to tackle such problems ‘when committed intentionally’. 
However, as Protocol II has only been ratified by approximately sixty states,  it has not yet attained the status of international customary law, hence the need for more states to ratify it to achieve this end. As the 1954 Convention in its totality regulates the targeting of cultural property in wartime, the increasing occurrence of art smuggling during peacetime constituted the necessity to regulate the circulation and facilitate the repatriation of stolen/illegally exported/imported artefacts internationally. This is addressed by several conventions dealing directly with the matter; the first is the 1970 Paris Convention.
The 1970 Paris UNESCO Convention
The 1970 Convention on the Means of Prohibiting and Preventing the Illicit Import, Export and Transfer of Ownership of Cultural Property is the first international instrument that sought to provide a legal framework to tackle the illicit trade cultural property.  More specifically, it sought to provide regulations to control the trade in art and antiquities (Art. 8); particularly the import/export or transfer of legal title for artefacts.  To achieve that, the Convention imposes the implementation of administrative measures on each state.
Art. 5 requires the creation of governmental bodies promoting the protection of cultural property and the creation of inventories - lists documenting the protected artefacts, while Art. 6 requires the establishment of an ‘import/export control system’  (requirement for a valid certificate issued by the authorised governmental body allowing the exportation of an artefact), along with the imposition of penalties where required under Art. 7(b)(i). 
However, the Convention even before its enforcement failed to address a very important issue: the situation with ‘bona fide purchasers’ as the states involved disagreed gravely on the matter (some supported the good title of an innocent purchaser whereas other states were persistent that ‘no good title […] [is] transferred by a thief’), with the drafters leaving the problem unresolved.  This allowed those involved in art smuggling to exploit the differing approaches taken in different jurisdictions to accommodate their ends. 
Furthermore, as the Convention relies solely on governmental action (e.g. employment of ‘diplomatic offices’ for the restitution of stolen artefacts), it has failed to (directly) consider the interests of private individuals. As a result, the requirement of state intervention for the retrieval of personal property has proven problematic. 
Further, the Convention, does not cover the restitution of illicitly removed/exported non-inventoried ‘clandestine excavated’ artefacts (even though it recognises the wrongfulness of such acts and encourages institutions not to get involved with such objects through Art. 7(a)). The instrument only addresses the restitution of ‘designated cultural property objects’ that are linked (emphasis added) to ‘a religious or secular public monument or similar institution […] documented as appertaining to the inventory of that institution'. 
A state can inform, though, under Art. 9 other states about any perils (looting, etc. of archaeological sites) that may endanger its ‘cultural patrimony’ and accommodate cooperation to achieve the protection and repatriation of such objects.  This provision was inserted mainly to accommodate the interests of leading ‘market states’ that were ‘unwilling’ to facilitate the return of all designated cultural property claims, as this meant that they had to recognise the export laws of other states’, something that they were, and some still are, strongly against to. 
The first two instruments brought, in the second half of the 20th century, significant legal developments internationally, as far as state/governmental action is concerned. But what about private property? Next week’s article (Part II) will explore the conventions that followed with the goal to address the loopholes left uncovered by the instruments analysed in this article and comment on their efficacy.
 John Henry Merryman, ‘Cultural Property Internationalism’  12 International Journal of Cultural Property 11,13.  Ibid 13.  Ibid 18,19.  Gael M. Graham, ‘Protection and Reversion of Cultural Property: Issues of Definition and Justification’,  21 Int'l L. 755, 767-768.  Mateusz Maria Bieczyński, ‘The Nicosia Convention 2017: A New International Instrument Regarding Criminal Offences against Cultural Property’  3 Santander Art and Culture Law Review 255, 257.  Lyndel V. Prott, ‘UNESCO and UNIDROIT: A Partnership against Trafficking in Cultural Objects’  1 ULR 59,68.  Stefano Manacorda, ‘Criminal Law Protection of Cultural Heritage: An International Perspective’ in Stefano Manacorda and Duncan Chappel (Eds), Crime in the Art and Antiquities World - Illegal Trafficking in Cultural Property (Springer, 2011) 17, 27.  Ibid 26.  Ibid 28; Prott (n6) 67.  Prott (n6) 66,67.  Manacorda (n7) 28; Prott (n6) 67.  Art 15(d) Protocol I 1954 Convention.  Manacorda (n7) 29.  ibid 29.  ibid 29.  Ibid 28.  Ibid 30.  ibid 31.  e.g. ban the import of artefacts designated by other states as illicitly exported and/or stolen; Ibid 32.  Prott (n6) 69; Manacorda (n7) 31.  Prott (n6) 59,60.  ibid 60.  ibid 62,65.  ibid 62.  Ibid 65.  ibid 62.