Few things fuel conspiracy theories like learning that governments are actually hiding something. Though a tremendous amount of civic documentation in the United States is accessible to the public through various agencies' websites or via the Freedom Of Information Act (FOIA), when materials get locked away with years-long temporary seals speculation about their nature runs wild. While there are often legitimate reasons for withholding information from the public for a period of time - not wanting to interrupt ongoing investigations, keeping operational practices quiet, concealing vulnerable identities, etc. - withholding information from the public for long periods of time creates conjecture.
The FBI has a "vault" of sealed files, as do governments across the world. While it likely contains information on major cases ranging from the mundane to the highly controversial, a good deal of it will simply remain unknown for decades.
You may remember the excitement surrounding the release of previously sealed documents pertaining to Lee Harvey Oswald’s 1963 assassination of President John F. Kennedy. Starting in 2017, the Trump administration, in compliance with the 1992 JFK Records Collection Act, declassified thousands of primary materials from the case, including documents that detailed Oswald’s attempts to obtain a Soviet or Cuban visa during a trip to Mexico City, suggesting his intention to escape the US after carrying out the assassination.
Perhaps the most notable element of the release, however, was what the administration decided to hold back. Despite the Act’s stipulation that all materials surrounding the investigation be made public within 25 years, the government resealed some documents for further review until 2021. What those withheld documents contain is impossible to say with certainty, but the current consensus holds that they probably have more information on Oswald’s activity in Mexico collected by US intelligence offices in Mexico City.
The family of US diplomat Charles Thomas is actively pressuring the administration to expedite the release of the remaining documents. Thomas, who died by suicide in 1971, repeatedly attempted to investigate whether or not the Warren Commission failed to explore a connection between Oswald and a group of Cuban citizens loyal to Fidel Castro.
Martin Luther King Jr. drew a considerable amount of FBI scrutiny as a major leader of the Civil Rights Movement. Suspected of bearing ties to communists, the Bureau surveilled his and his associates’ movements and conversations starting in the late 1950s until his assassination in 1968.
The full scope of their findings has never been accessible to the general public due largely to a 50-year seal on the wiretap records District Judge John Lewis Smith enacted in 1977. When Smith issued his order, he was acting to both preserve the trove, which King's former assistant Bernard Lee wanted destroyed, and mitigate its impact on King's assassination.
What has made it from the FBI’s surveillance records has not cast them in a positive light. In 2017, a 20-page document released as part of the JFK records dump underscored the Bureau’s preoccupation with establishing King’s ties to the Communist Party USA throughout the '60s, despite scant evidence.
Chief Justice Warren Burger is widely considered one of the most influential legal figures of the 20th century. A Nixon appointee, the right initially expected him to deliver a course-correction from its prior left-leaning years. However, in numerous landmark cases, Burger proved to be more of a judicial moderate than the Republican party hoped. He sided with the majority on Roe v. Wade in favor of broad abortion protections, United States v. Nixon against the president in the Watergate Scandal, and Swann v. Charlotte-Mecklenburg Board of Education in favor of school-integration busing programs.
Naturally, the unpublished records documenting Burger's thought process in these and other cases are of considerable interest to historians and legal scholars. The trove of what is described as "professional and personal papers" won’t be accessible until 2028, per its current guardians, Virginia’s College of William and Mary.
The famously scandal-plagued and short rule of Edward VIII has had more than its fair share of popular gossip, but there’s still one episode about which the public will have to wait to learn the full details. They’re contained in “Box 24,” which is officially under seal until 2037. Edward assumed his role as king of the United Kingdom in January 1936, but abdicated in December of the same year.
He married the twice-divorced American Wallis Simpson, and their romance caused a crisis. The official records surrounding his short tenure as well as their romance have served as grist for Best Picture winner The King's Speech and one of Netflix’s most popular series, The Crown.
The public speculates Box 24 contains documents concerning Edward's support for negotiating peace with pre-World War II Nazi Germany and letters from the Queen Mother attacking Simpson's character, making their concealment an attempt to save face.