For decades, this haunted piece of history — the weapon allegedly used to kill Emmett Till — lay in a wooden drawer, gathering dust.

That changed in 2004 when FBI agent Dale Killinger began reinvestigating Till’s lynching.

The longtime owner of the weapon, who asked not to be named for fear of harassment or retribution, said the FBI kept the gun “for a year almost to the day.”

On Thursday, the .45-caliber pistol that J.W. Milam is believed to have used to pistol-whip and shoot the Black Chicago teen became part of the Emmett Till Exhibit at the Mississippi Civil Rights Museum. 

In World War II, Milam served as a lieutenant in the Army Air Force and brought back the Ithaca Model M1911-A1 .45-caliber pistol.

Milam and his half-brother, Roy Bryant, abducted Till from his great uncle’s home in the wee hours of Aug. 28, 1955. The white men heard that Till had reportedly wolf-whistled at Bryant’s wife Carolyn.

They took Till to a barn, where Bryant, Milam and others brutally beat him. Witnesses heard Till’s screams.

Till was beaten so badly there was talk of dropping him off at a hospital, but Milam killed him with a single bullet.

An all-white jury acquitted the half-brothers of Till’s murder. They later admitted to Look magazine they had indeed killed Till, who had just celebrated his 14th birthday.

During the FBI’s investigation of the Till murder, authorities exhumed his body. X-rays revealed extensive skull fractures and metallic fragments in the skull. There were also fractures to the left femur and the left and right wrist bones. The Cook County Medical Examiner’s Office in Illinois concluded that Till died of a gunshot wound to the head.

During the autopsy, doctors found four lead fragments that experts determined were consistent with lead shot pellets. The FBI learned that the size of those pellets matched the size of the lead shot manufactured for the Army Air Force.

The longtime owner said his father was a gun collector and a friend of one of the lawyers who defended the half-brothers. He said his father got the gun from one of those lawyers around 1959 or 1960.

Years after his father died, he said his mother announced that she wanted the gun out of the house. She gave it to his sister, and from that moment on, the siblings became the gun’s owners.

The longtime gun owner said the family knew they had something of historical value, but “none of our children cared about or wanted the gun.”

In recent years, they had offers from private collectors to sell the gun, but “we didn’t want to go that route,” he said.

Instead, they decided to make the gun available to the foundation for the Mississippi Department of Archives and History, which in turn has added the weapon to the Civil Rights Museum.

The gun makes a lighted appearance during a 6-minute film about the case, narrated by Oprah Winfrey.

It’s the second such weapon in the department’s possession. The first is the .30-06 rifle used in 1963 to kill Mississippi NAACP leader Medgar Evers, which can also be seen at the museum.

The FBI’s borrowing of the gun proved fortuitous. During the year the FBI had the weapon, the longtime owner said his sister suffered a break-in during which guns were stolen.

The thief never got a shot at the .45 that changed the course of history.

From that moment forward, the gun spent its days in a safety deposit box in a bank in Greenwood, the longtime owner recalled. “It could have been lost, but the truth is, it was never hidden.”