The aviator Charles Lindbergh poses with his airplane, 'Spirit of St. Louis,' in May 1927. Getty Images

Eighty years after one of the nation's most infamous crimes, public fascination with the kidnapping and death of Charles Lindbergh's young son has been re-kindled with a bevy of new scholarship released in 2012. And there's more to come next year.

Two books published this year examined unanswered questions in the case of Charles Lindbergh Jr., the 20-month-old boy who was abducted from his parents' New Jersey estate in 1932, igniting a national sensation that ended in one of the most dramatic trials in U.S. history.

Several recent books have rekindled interest in the case, with one claiming that Charles Lindbergh may have been involved. Getty Images

In the afterword to one of those books, "The Case That Never Dies," Rutgers University historian Lloyd Gardner has stirred controversy with a claim that the famous aviator was involved in the kidnapping.

Meanwhile, the first photographic history of the case was published in November, as was a compilation of the diaries and letters of Lindbergh's wife, the late Anne Morrow Lindbergh, in April.

Public Broadcasting Service is airing a "NOVA" program on Jan. 30, promising a fresh look at the Lindbergh case through new forensic research.

And in June, a book is set to be published offering the first in-depth look at Arthur Koehler, a pioneering forensic biologist who traced the wood from the ladder leading to the Lindbergh nursery.

"It's the same as the Kennedy assassination and the same with 9/11 today. There are still questions that people struggle to answer, and they want them to be answered conclusively," said Adam Schrager, a Wisconsin Public Television producer and the author of the forthcoming book on Mr. Koehler.

Lindbergh rose to fame after his solo trans-Atlantic flight between New York and Paris in 1927. The kidnapping of his son on March 1, 1932, from quiet Hopewell, N.J., north of Trenton, made international headlines. A $50,000 ransom was paid, but the boy didn't turn up.

Charles Lindbergh Jr., above, was kidnapped from the family estate in 1932. Popperfoto/Getty Images

Two months after the kidnapping, Charles Jr.'s body was found in a wooded area not far from the Lindbergh home. Doctors determined he had died of a skull fracture. Bruno Hauptmann, a South Bronx man who didn't know the Lindberghs, was the only person arrested for the crime, after a two-year investigation revealed that he possessed some money with serial numbers that matched notes from the ransom. He was convicted of murder and sentenced to death in 1935. The German immigrant maintained his innocence up until his execution the following year.

At the time, theories abounded that there were others involved and additional motives in the botched kidnapping—questions that continue to fascinate scholars.

Mr. Gardner, a history professor emeritus at Rutgers, believes that Lindbergh could have had a role in his son's kidnapping. In a new afterword to his 2004 book, Mr. Gardner writes that serious health disorders manifesting in his son and Lindbergh's fascination with eugenics might have driven the aviator to remove the child in whatever way possible.

Lindbergh had struck up a close friendship with a prominent eugenicist, Alexis Carrel of the Rockefeller Institute, Mr. Gardner wrote. In a pre-trial deposition viewed by Mr. Gardner, the Lindberghs' family doctor said Charles Jr. had trouble standing, an abnormally large head and overlapping toes, all factors in line with a "moderate rickety condition."

Lindbergh may have wanted to quietly move his son into an institution, in a move that backfired terribly, Mr. Gardner said in an interview and in the book. Contributing to his theory, he said, is that the kidnapping occurred during one of the first weekdays the Lindberghs stayed in the newly constructed house and that the normally meticulous Lindbergh missed a speaking engagement that day.

"I'm fairly well-convinced that Charles Linderberg was so concerned about his child that he wanted something done," Mr. Gardner said in an interview. "This would have been a great source of anxiety."

Reeve Lindbergh, the youngest of Charles and Anne Morrow Lindbergh's children and a family spokeswoman, declined to comment on the theory that her father was involved.

Mr. Gardner's theory isn't accepted by many Lindbergh historians and is at odds with a new book by author Robert Zorn, "Cemetery John," published last June by Overlook. In the book, Mr. Zorn asserts that the kidnapping was masterminded by a man named John Knoll, who was never charged with the crime.

Mr. Zorn consulted with FBI profilers, psychologists, handwriting experts and Mr. Knoll's family members as part of his theory that the German deli clerk from the South Bronx actually hatched the kidnapping scheme.

Mr. Knoll resembles police sketches of the elusive "Cemetery John"—who wrote the kidnapping ransom notes and collected the money—down to a deformed thumb, Mr. Zorn wrote. A portion of the ransom money was never recovered, and Mr. Zorn believes that Mr. Knoll used his cut to pay for two first-class boat tickets to Hamburg in 1934. Mr. Knoll returned to New York after Mr. Hauptmann's conviction.

"John Knoll is not just anyone. He is the first real person of interest to emerge in the 78 years since the arrest of Hauptmann," wrote Mr. Zorn, who believes Mr. Knoll led a gang of three that included Mr. Hauptmann to kidnap Charles Jr. According to Mr. Zorn's theory, the infant died when a homemade ladder used to snatch the child gave way, and Mr. Knoll dropped him

Mr. Knoll died in Toms River, N.J., in 1980. He was never questioned in regard to the crime, and Hauptmann didn't implicate him. Mr. Knoll's relatives couldn't be reached for comment. Some talked to Mr. Zorn, but the book doesn't offer their opinion on the book's theory.

Mark Falzini, an archivist for one of the largest repositories of material on the Lindbergh case at the New Jersey State Police Museum, said Mr. Gardner's theory about the aviator's role in the kidnapping shouldn't be dismissed out of hand.

"It's something that needs to be seriously looked at and not just discarded," he said. "He's not doing it on a whim to sell books. It's an actual possibility."

Mr. Falzini said he still receives letters of inquiry about the case from people across the world. Several dozen people visit the archives annually to conduct their own research.

"It's America's greatest soap opera," said Mr. Falzini, who co-authored "New Jersey's Lindbergh Kidnapping and Trial," the first pictorial history of the case, issued in November.