Most large European museums hold objects acquired during colonial rule.
For decades the standard reply to claims was legal and procedural.
Acquisition had been lawful at the time, and were bound by their charters.
That answer has weakened as the of individual items has been documented.
Objects taken during a expedition are difficult to describe as a purchase.
A second argument concerned and access.
It held that objects were safer in a large institution and seen by more people.
Both halves of that claim are now empirically .
Many disputed items sit in storage and have not been displayed for a generation.
Several returns have now taken place, and the sky did not fall.
Benin bronzes, Maori remains and Aboriginal objects have gone back under varied arrangements.
Some were transferred outright; others were lent back to the holding museum immediately.
The practical question is rarely the object and usually the record.
catalogues let a claim be made at all, which is why some institutions resist publishing them.
Ownership, in the end, is decided less by law than by what a museum is willing to say in public.