The moment Adolf Hitler’s voice burst over the airwaves one summer night in 1937 declaring steadfast opposition to so-called “degenerate art,” 53-year-old painter Max Beckmann knew his time in his native Germany had come to an end. Finding life under such circumstances increasingly untenable, Beckmann, with his wife Quappi at his side, fled the country that had imbued him with a love of painting, brought him as a volunteer hospital steward to the front lines of World War I, and nurtured his career as an artist — until the ascendency of Hitler’s Nazi regime snuffed out any hope he had of continuing to work in the doomed republic.

Self-imposed exile took the Beckmanns from Germany to Amsterdam, then to St. Louis in 1947, before they finally settled in New York. Here Beckmann, still haunted by his experiences in the war, angry at the post-war excesses thrown in his face daily in Weimar-era Berlin, and withdrawn into his painting practice perhaps more than ever, took on a professorship at the now-defunct Brooklyn Museum Art School.

Beckmann’s life in the big city is the subject of a long-overdue examination that continues at the Metropolitan Museum through Monday. The Met’s spare but very commendable exhibition includes some of the artist’s most exemplary works, including superlative pieces like “Departure” (1932, 1933–35) and “Bird’s Hell” (1938) not likely to be seen together in New York again for decades. But one piece in the show, which might go largely unnoticed if not for an intriguing allusion in the wall text, has a particular significance that still reverberates in the walls of the Met and every other American art museum to this day.

In 1971 — 21 years after Beckmann suffered a massive and fatal heart attack while on his way to the Met to view another piece included in the exhibition, “Self-Portrait in a Blue Jacket” (1950) — the museum was undergoing a radical change in approach that mirrored profound transformations in society writ large. Thomas Hoving was four years into a directorship that rattled so many cages at the institution that it is a wonder he was able to last another six years. The museum industry itself was on the verge of being ruffled by the emerging auction boom, fueled in large part by the so-called New York school artists. The group’s rising market value was by no small measure a product of the Met’s then head of the Department of 20th-Century Art, 36-year-old Belgian émigré Henry Geldzahler — “the most powerful and controversial art curator alive,” according to one journalist.

“Deaccessioning” was, at the time, a new term for a very old practice that remained, at least as far as the Met’s board was concerned, in a kind of gray area — without much oversight or regulation in the way of official guidelines. All of this changed, however, the instant Geldzahler presented the Met’s acquisitions committee with a scheme, the outcome of which (though none knew it at the time) would change the way the museum handled the deaccessioning of objects and alter the relationship of the Metropolitan Museum to the public forever.

Geldzahler was in the midst of selling off large portions of the gift the museum had received at the beginning of Hoving’s tenure in 1967 following the death of Hartford shipping heiress Adelaide Milton de Groot. In particular, he had set aside three pieces by Beckmann, including a painting typical of the artist’s moody, self-reflective style that he had made just before leaving Europe for what proved to be the last time, “Self-Portrait with Cigarette” (1947). The sale of the self-portrait, along with the two additional Beckmanns, was intended to enable the museum to acquire “Becca,” a 1965 piece by the sculptor David Smith, a popular artist in the New York school cohort that Geldzahler worked so hard to promote.

But the sell-off ran into stern opposition in the form of one André Mayer, the French-born financier who chaired the Met’s acquisitions committee and wanted from Geldzahler an estimate for the value of the three works. Geldzahler came back with a figure — the Beckmanns, he said, were worth no more than $25,000 apiece — that prompted Mayer to question the curator’s valuation method and asking for an outside evaluation of the pieces.

Instead, the Beckmanns were sold via what Hoving termed a “silent auction” for $95,000 to Serge Sabarsky, the Vienna-born art dealer whose collection went on to make up the heart of the collection of the Neue Galerie (which contributed two of the Beckmann show’s 39 pieces). Hoving, meanwhile, maintained (in public, anyway) that the sale had never happened, eventually attracting the attention of New York Attorney General Louis J. Lefkowitz, who finally pushed the museum to adopt a set of procedures for the sale of its artworks. Six years later, Lefkowitz prosecuted the Brooklyn Museum in the so-called “Kan case,” which further served to formalize institutional practice concerning deaccession.

As a direct result of the public blowback over the de Groot sell-off — which culminated in a public hearing and tit-for-tat editorial salvos in the New York Times from Hoving, then-Met President Douglas Dillon, and the critic John Canaday — the museum published for the first time in June of 1973 a four-page booklet outlining its amended procedures for deaccession. With the publication of the booklet, the Met’s board codified a set of policies (now accessible online) formally forbidding employees or anyone with direct involvement in the museum’s stewardship from directly purchasing any piece that the museum deaccessions. Furthermore, the new guidelines set forth formal criteria to determine which works in its collection can be deaccessioned, and giving the museum the right to use the funds obtained from deaccessioned works toward the purchase of other works to be retained in its permanent collection.

Geldzahler left the museum in 1977 in order to take a role in the administration of New York City Mayor Ed Koch, as the Commissioner of Cultural Affairs. To this day, his legacy as a curator remains by turns controversial and groundbreaking. For better or worse, he can be credited with bringing the issue of deaccessioning out of the opaque realm of museum administration and into the public and professional discourses.

The onset of the Reagan administration in 1981 brought about dramatic cuts to the National Endowments for the Arts and Humanities and other public funding for the arts that drastically affected the role of deaccessioning within non-profit institutions. As a result, museums began to rely more and more on the decisions and changes made in the aftermath of Lefkowitz’s investigation as the lack of government funds necessitated the use of collections as an alternative revenue source. The art market boom of the late 1980s only further accelerated sell-offs, and engendered even further changes to museum protocol regarding deaccessioning. The American Alliance of Museums (AAM) began for the first time in 1984 to require written collections management policies (which include deaccessioning policies) from institutions in order to receive and retain accreditation.

The late 1980s and early ‘90s also saw a boom in museums finally establishing their own formal guidelines and policies concerning collection management and deaccession. In 1991, the AAM, working with the Association of Art Museum Directors (AAMD), adopted stipulations similar to those seen in the original 1973 Met booklet that limited the uses of funds raised from the deaccessioning of objects to the acquisition and maintenance of other objects. Further stipulations in 1994 included a clause that further emphasized this point, stating that

disposal of collections through sale, trade, or research activities is solely for the advancement of the museum’s mission. Proceeds from the sale of nonliving collections are to be used consistent with the established standards of the museum’s discipline, but in no event shall they be used for anything other than acquisition or direct care of collections.

Widespread adoption of these guidelines did not altogether accomplish its intended purpose of assuaging public criticism concerning deaccessioning, as incidents at the Museum of Modern Art in 1989 and Albright–Knox Art Gallery in 2007 demonstrated. Nor did it prevent museums from breaking the rules from time to time, as the Delaware Art Museum so egregiously demonstrated more recently. But the guidelines have changed the museum profession irrevocably, perhaps as much as Beckmann changed German painting or as life in exile changed him. Although the Met no longer owns his painting — it was eventually acquired by the Museum am Ostwall in western Germany — the artist’s self-portrait offers a bold image of a pensive man constantly adjusting to the displacements and tumults of his life, which mirror in no small way the changes and disruptions to museum practices that the painting’s deaccession set off.

Max Beckmann in New York continues at the Metropolitan Museum of Art (1000 Fifth Avenue, Upper East Side, Manhattan) through February 20.

A special thank you is owed for the superhuman research efforts of Gordon Dearborn Wilkins, without whom this article would not have been possible.