Bruno Richard Hauptmann’s mug shot. The wooden electric chair where he was put to death. A sponge like the one that was dampened with salt water and placed on his head to conduct the deadly jolts of electricity.

This grim assortment of relics is housed in a small museum in New Jersey, about 20 miles away from where the decaying body of Charles A. Lindbergh Jr., the toddler Hauptmann was convicted of kidnapping and killing, was discovered face down in the dirt.

Nearly 100 years ago, the Lindbergh case was known as the crime of the century by virtue of its cinematic details and the boy’s high-profile parents, Anne Morrow Lindbergh, a diplomat’s daughter, and Charles A. Lindbergh, an aviator who had catapulted to fame by completing the world’s first nonstop flight from New York to Paris.

In the decades since, as the keepers of the Lindbergh kidnapping archives can attest, public interest in the case has never subsided — nor has skepticism about Hauptmann’s guilt. But a bizarre and grisly new theory about Lindbergh’s potential involvement in his son’s death, and renewed legal pressure to force DNA testing of evidence, have combined to thrust one of the country’s most enduring murder mysteries squarely back into public consciousness.

Hauptmann, a German immigrant who had worked as a carpenter and lived in the Bronx, was executed for the crime in April 1936. His great-great niece, Cezanne Love, and her aunt recently provided DNA samples in the hope that New Jersey’s courts would decide to clear the way for modern science to explore century-old doubts: Was an innocent man put to death? And, if not, did he act alone?