On the evening of November 19, 1931, a Cadillac pulled up to the two-level gas station on Washtenaw (today home to Bearclaw Coffee). According to the Michigan Daily, the driver and passengers had obscured their faces with “dark goggles” and “hats pulled down over their eyes.” They rolled a five-gallon ceramic jug out of the car and sped off.

K.D. Smith, the attendant on duty, scooped up the crock. Painted on its side was a tally of football scores between the U-M and the University of Minnesota dating back to 1903. For weeks, the Michigan athletic department had been conducting a very public hunt for the Little Brown Jug, a trophy the teams had fought over since 1909. Now, it seemed, it had been found.

But while the Daily reported that university officials “practically proved the authenticity” of the jug, the Ann Arbor Daily News dismissed it as an “imitation.” When Michigan defeated the Golden Gophers, 6-0, a few days later to retain the trophy, the News wrote that the Wolverines had been “spared the embarrassment” of having to surrender the “bogus” replica.

When the Wolverines played in Minneapolis the following year, the Minnesota Daily reported that “talk of the genuineness or phoneyness of the jug waxed hot in barber shops and fraternity houses.” The chief skeptic was Minnesota equipment manager Oscar Munson. “They’ve been shoving a spurious water container off on us for years,” claimed Munson, the man who helped start the tradition by finding the drinking jug the Wolverines left behind after a tie game in 1903.

Yet according to the Minnesota paper, Michigan athletic director Fielding Yost “didn’t even wink” when he assured reporters that it was authentic. “Why sure, it’s the real jug,” insisted Yost, who coached that 1903 game. “Take a look at it. Does it look like a phoney?” Michigan won the 1932 game, 3-0, and took the suspect prize back to Ann Arbor.

But in August 1933, the trophy was back in the news–when another version mysteriously appeared. According to the Chicago Tribune, this one was found “in a clump of bushes near the medical building” (today’s C.C. Little Science Building).

Yost then vouched for the authenticity of the new jug. “I hope that some day the person who had the jug the two years it was missing will write me a letter and tell me the story of what was done with it while it was gone,” he told reporters. The Wolverines and Golden Gophers tied that season, leaving the jug in Michigan’s possession. But the following year, the Gophers hammered center and linebacker Gerald Ford and the Wolverines, 34-0, to reclaim the prize.

Michigan leads the trophy series, 66-22, with three ties. The jug has been in Ann Arbor since 2006 and will remain here at least until 2011; due to a scheduling snafu, Minnesota and Michigan do not play this season or next. But don’t go to Schembechler Hall expecting to see the famous vessel–the one on display is a replica. The trophy itself is kept in an undisclosed location.

No wonder that 100 years after Michigan and Minnesota first played for the prize, some still wonder whether today’s official Little Brown Jug is the original or a fake.

This past winter I wrote about the 1909 season in Hail to the Victors 2009, a Michigan preseason football guide. The 1909 Minnesota game was the first time the teams met since the jug was left behind in 1903, and the first in which the trophy was at stake. Wondering whether it had really survived for a century, I read what I could find about its history. Since the news accounts from the 1930s were so contradictory, I started to snoop around, beginning by talking to the men who have protected it over the years.

Michigan equipment manager Jon Falk has had custody of the jug for most of his thirty-six years on the job. Falk says that his understanding is that the trophy he’s got tucked away is indeed the real thing. Retiree Bob Hurst, who started at the department in 1945 and worked directly with Hank Hatch, equipment manager from 1919 to 1964, says he was always told the jug was genuine.

On the other sideline, Oscar Munson had dismissed the “Cadillac” trophy but vouched for the one found in the bushes: “It’s the original jug, all right,” he said before the 1935 game, “and I’m the only one who knows.” Longtime Gopher equipment manager Dick Mattson, who served from 1963 to 2008, agrees. Though Minnesota held the prize only six times during his tenure, “it’s the original jug,” Mattson insists.

Others well versed in the Michigan tradition are less positive. “We’re just not sure” if the trophy is the original, says Bruce Madej, the longtime Wolverine sports media relations director. Greg Kinney, curator of the athletic archives housed at the U-M Bentley Historical Library, says he isn’t certain, either. And former head coach Lloyd Carr told me he always believed the trophy wasn’t the original jug.

With the experts disagreeing, that left the jug itself. It was time for a forensic investigation, like the ones you see on those TV crime dramas.

The athletic department granted my request to inspect the jug, and with Jon Falk on hand I took a variety of photos from several angles. Using a graphics editing program, I then compared these with a photo of the jug taken before 1910. The spout, handle, and shoulder looked dead on, but the current jug seemed slightly shorter. Of course, perspectives can change drastically depending on the angle of the camera and distortion in the lenses.

Seeking an expert perspective, I took the photos to Ryan Forrey, master potter at Greenfield Village in Dearborn. Forrey inspected the new and old images, paying particular attention to the handle, a distinctive element of handmade jugs. Forrey thought they looked the same but said he needed to hold the jug to be sure.

Several weeks later, Falk met Forrey and me at Schembechler Hall. Falk had taken the jug out of the protective crate where it’s kept and set it atop a table in the equipment room.

Forrey quickly found two critical features that I’d missed. Beneath the Minnesota “M” logo painted on one side of the jug, he pointed out a small flaw or notch that matched one visible in the pre-1910 photo. And just above the same “M,” he spotted a pair of raised, triangular areas under the paint–traces of an earlier, sharp-pointed “M” that had been painted over.

Forrey had seen enough. Considering the photo comparisons, distinctive shape of the handle, the notch, and the ghostly Minnesota logo, he said, “I’d be shocked if this isn’t the original jug.”

Digging through articles and photos from the 1920s, I later found two images of the jug displaying a pointed Minnesota “M”: one in the program for the 1923 game, and another 1927 photo of Minnesota captain Herb Joesting cradling the crock. Since both images predate the shady doings of the early 1930s, I’m confident the jug in Michigan’s custody is authentic.

I’m also certain that for at least two years in the 1930s, the U-M tried to pass off a replica as the real thing. I don’t know who created the “Cadillac” jug, or where the real trophy was at the time. For what it’s worth, though, Minnesota’s Oscar Munson never had any doubt: he always claimed the Little Brown Jug had spent those years “in Mr. Yost’s cellar.”