One of the many things the events of 2020 have torqued to the point of rupture is museum finances. As a result, today’s straitened circumstances have pumped oxygen into a debate that has continued, sotto voce, for decades, regardless of circumstances. For some people the solution lies in museums’ and galleries’ own hands: they are sitting on collections of incalculable value so why not sell some pictures and, with one bound, be free?

Deaccession is a dirty word in the heritage world. When an object enters a public collection by legacy, gift or purchase it is expected to stay there; as it crosses the threshold it leaves the grubby marketplace for ever. However, that boundary is not totally impermeable. In April the French government announced that it will hold a sale in the autumn to auction off 100 pieces of 19th-century furniture from the state collection. If this is likely to be a one-off, for the benefit of the nation’s hospitals, and merely the clearance of stock with no outstanding artistic or historical value, recent changes in America might have broader repercussions.

The Association of Art Museum Directors (AAMD), comprising the heads of museums in the United States, Mexico and Canada, has just released new guidelines to deaccessioning. They state that in the future any museum that “decides to use restricted endowment funds, trusts, or donations for general operating expenses” will be allowed to do so without sanction and, what’s more, museums can now use the proceeds from the sale of works “to support the direct care” of their collection.

This second stipulation, a reversal of AAMD’s “long-standing principle”, marks the greater change of direction. Previously the sale of one work was occasionally allowed specifically to raise funds for the purchase of another. In 2011, for instance, the Museum of Fine Arts in Boston sold eight works, including paintings by Monet, Gauguin, Sisley, Pissarro and Renoir, in order to raise funds to buy a single painting, Gustave Caillebotte’s Man at His Bath.

The San Francisco Museum of Modern Art meanwhile is currently selling a painting by Mark Rothko (Untitled, 1960), to fund new acquisitions. AAMD stresses that its new guidelines are “not intended to incentivise” the offloading of works from permanent collections, but having given museums licence it makes it that much harder to withdraw it again.

There is, however, no sign yet that guidelines in Britain might be similarly reworked. Public collections here are governed by UK statute law which has strict deaccession procedures. Deaccession itself is not prohibited but the Museums and Galleries Act 1992 allows it only in certain circumstances: where a collection holds a duplicate object, for example, or where the artwork “is unsuitable for retention” — though it is unclear what that might mean — “and can be disposed of without detriment to the interests of students or other members of the public”.

The Act allows for irreparably damaged works to be “disposed of by any means including destruction” and for the transfer of pieces between national museums, for better public access or improved context. If a work is sold then any proceeds must be put towards “the acquisition of relevant objects” for the institution’s collection. Even when the detailed stipulations have been met, the Museums Association warns institutions to “proceed with caution” and be aware of “public reaction and consequences of negative publicity”.

Perhaps this latter shot across the bows is why, for example, Tate Modern has sold only one work from its permanent collection — a duplicate print by Roy Lichtenstein. There is, nevertheless, a regular drip-drip of works held by less high-profile institutions and a would-be purchaser can consult the Museum Association’s website to see what’s on offer. The Royal Museums Greenwich, for example, is disposing of an undistinguished 1954 painting of the Cutty Sark in full sail; the National Museums of Scotland is jettisoning miscellaneous “aviation-related” items (including an air-raid warden’s whistle); while Wakefield Council is ridding itself of a Tudor-style door.

If such items are bric-a-brac not everything is. In January, Leighton House Museum sold a sunset river scene by Joseph Wright of Derby (1734-1797): the painting fetched £300,000 — not a Rothko-like price but hefty none the less. It emerges that the museum had, quite properly, first tried to find the painting a home in another public collection and offered it for £70,000. Possibly because no other institution wanted to be seen dealing in deaccessed art there was no taker even at this knock-down price, and the picture went on the open market. Its purchaser is likely to have been a private collector and the painting may never be seen in public again.

So while the great paintings in the nation’s collections are safe there remains enough wiggle room in the guidelines for less lauded items to be imperilled. Of course many galleries own far more works than they can display and the loss of some minor pictures might not be felt keenly — at least now. However, artistic fashions change and disposing of the work of an artist seen today as a peripheral figure may in the future be viewed as having sold off the family silver.