I’m going to give you some more, because this story is behind a paywall.

Wow, what a story. I can’t wait to read the book. I wonder if those paintings will ever be found? I always assumed that some rich collectors had requested specific paintings that they wanted the thieves to steal.

Tom Mashberg at The New York Times (gift link): Got an Idea About Who Robbed the Gardner Museum? Get in Line.

It seems just about everyone has been fingered at one time or another as the perpetrator of the largest art theft in U.S. history: the 1990 robbery of the Isabella Stewart Gardner Museum in Boston. Two men dressed as police officers showed up at the door of the museum just after 1 a.m. on March 18 as the city rested after celebrating St. Patrick’s Day. They tied up the two guards on duty and walked off with 13 items, including masterpieces by Rembrandt and Vermeer.

Landscape with Obelisk by Govert Flinck

In the ensuing decades all kinds of theories were hatched about who was behind the theft. The Corsican mob. The Irish mob. Noted art thieves. Unknown petty criminals. People who worked in the building. The Irish Republican Army.

Geoffrey Kelly, the F.B.I. agent who handled the case for 22 years, heard all of them and investigated many of them. In his new book, “Thirteen Perfect Fugitives,” Kelly dismisses many of the theories and outlines who he really thinks committed the crime but could never be prosecuted.

Here are his thoughts on some of the theories and his view of what really went down.

Was it the Corsican mob?

One of the items taken from the museum was, oddly, a finial from a flagpole that had once flown the flag of the First Regiment of Napoleon’s Imperial Guard. Not a top-shelf masterpiece. But in 2006, French national police investigators told the F.B.I. that they had heard some rumblings that a Corsican crime group (Napoleon was Corsican) was looking to sell some items from the museum.

An F.B.I. agent who specialized in art crime went undercover, posing as an intermediary for a buyer who was supposedly interested in buying stolen art. The investigation, called “Operation Masterpiece,” included a sting operation on a yacht and other intrigue. It turned up some criminal behavior involving art. But Kelly says the Corsicans were bluffing. They had access to some stolen art, but nothing from the Gardner heist.

Maybe the paintings never left?

What if the stolen works were really right under investigators’ noses? Kelly writes about “The Paintings Never Left the Museum Theory.” It became a perennial. Many tipsters called in to suggest that, since the works had not shown up on the market, or anywhere else, it was possible that they had been secreted somewhere inside the building.

“Why didn’t we think of that?,” Kelly asks in the book. “Actually, we did.”

In the mid-1990s, the Gardner updated its HVAC system and as part of the renovations a team of commercial specialists crawled through every nook and cranny of the building as they installed new ductwork. They found dust but no paintings.

Or could it have been Whitey Bulger and the Irish mob? Use the gift link to read more if you’re interested.

There’s also an excerpt from Kelly’s book at Crime Reads: What It Means for an FBI Agent to Inherit the Gardner Museum Heist.

I’d first heard about the Gardner Museum robbery when I was a recent college graduate living in New York, probably a week or so after it occurred. I was at the American Museum of Natural History on the Upper West Side, gazing up at the giant blue whale suspended from the ceiling, when I overheard two elderly ladies discussing the details of a monumental art heist that had just occurred in Boston.

Heist. It’s one of those words that commands attention. Use it in a sentence in a crowded elevator, and someone will invariably listen in. Naturally, I couldn’t help but eavesdrop on their conversation and listened as one woman related to her friend a fabulous tale of fake police officers, outrageous subterfuge, and stolen treasures.

Chez Tortoni, by Eduoard Manet

And here it was, a dozen years later, and I just got the case.

Until the implementation of a computerized database system, which arrived a few years after the Gardner robbery, FBI files were in paper form. When a new case was opened and assigned to an agent, written as O+A, the very first document, known as a serial, would be two-hole-punched at the top and slipped into a cardboard jacket, skewered in place with two steel prongs. When the file became too fat to be safely secured with the bent-over prongs, Volume II commenced, although most cases rarely merited a second volume. Each squad had a set of file cabinets that held the hundreds of pending cases for that particular squad, and the whole lot was managed by file clerks known in Bureau parlance as rotors, named after the rotary file cabinets over which they governed. Newspeak eventually changed their job title to Operational Support Technician, or OST, but we still called them rotors.

No agent wants to inherit a case; typically, they’re either unsolvable or there isn’t an AUSA willing to prosecute. It’s common for agents to shop their cases door-to-door at the US Attorney’s Office, moving down the carpeted hallway like vacuum cleaner salesmen, hoping to fund an AUSA who’ll bite. These forlorn cases float from one agent to the next, until eventually the statute of limitations expires; that is, the deadline for prosecution, which is typically five years for most federal crimes. Once the statute has expired, the case can finally be administratively closed. Days before a new agent arrives on a squad, the supervisor typically polls the senior agents to surrender a case or two for the new guy. And that’s how a brand-new agent manages to inherit a full caseload of crap.

The Gardner was no exception. Prior to my tenure, it was a moribund case that nobody wanted. The only difference with this cold case was that pesky statute of limitations, as there is no expiration date for possessing stolen property. The reasoning is logical—if there was a firm deadline for prosecution, thieves could conceivably hold on to stolen property for five years and a day, then claim it as their own.

They could register a stolen car at the DMV or sell a stolen painting at auction. Since the statute of limitations for the possession of stolen property never expires, theoretically the Gardner case would remain open indefinitely.

Yet despite all the challenges, I really wanted this case. And I was intrigued by the biggest challenge of all: the title. The Gardner Museum heist was still carried as UNSUBS. It was the ultimate whodunit.

My first task was to get an idea of the scope of the investigation. Typically, the squad rotor (the file cabinet, not the human) contains every volume of a particular pending case. But due to the sheer size of the Gardner investigation, all but its most current volumes had been relegated to the Closed File Room down on the fourth floor. It was an area rarely visited by most agents, but one which I got to know quite well. Rolling stacks of cabinets extended the entire length of the room, containing a comprehensive collection of all of Boston’s historical FBI cases, arranged numerically by classification. It was surprisingly easy to find the Gardner case, classified as an 87A matter (interstate transportation of stolen property), since it took up nearly an entire file cabinet, sandwiched between other vintage theft cases, many of them ensconced in sepia-tinted file jackets that dated back to the days of J. Edgar Hoover.

And there it was, at gut level: the Gardner case.’