J. Gordon Shanklin was appointed special agent in charge of the Dallas Field Division of the Federal Bureau of Investigation in 1963.
In March, 1963, FBI agent James Hosty was ordered to keep Lee Harvey Oswald under observation. Soon afterwards Hosty discovered that Oswald was purchasing The Worker, the newspaper of the American Communist Party. In June, Hosty heard from FBI headquarters that Oswald was in New Orleans, and requested information on him.
Hosty visited the home of Ruth Paine to discover where Oswald was living. He spoke to both Paine and Marina Oswald about Oswald. When Oswald heard about the visit he went to the FBI office in Dallas. When told that Hosty was at lunch Oswald left him a message in an envelope.
The contents of the envelope has remained a mystery. A receptionist working at the Dallas office claimed it included a threat to "blow up the FBI and the Dallas Police Department if you don't stop bothering my wife." Hosty later claimed it said: "If you have anything you want to learn about me, come talk to me directly. If you don't cease bothering my wife, I will take appropriate action and report this to the proper authorities."
Soon after Lee Harvey Oswald was arrested for the assassination of President John F. Kennedy, Shanklin called James Hosty into the office. Hosty was asked about what he knew about Oswald. When Oswald was shot dead by Jack Ruby two days later, Shanklin ordered Hosty to destroy Oswald's letter.
The Federal Bureau of Investigation I discovered that Hosty's name and phone number appeared in Oswald's address book. J. Edgar Hoover was worried that this indicated that Oswald had been working closely with the FBI. That he might have been an FBI informant on the activities of left-wing groups such as the Fair Play for Cuba Committee. Instead of passing Oswald's address book to the Warren Commission, the FBI provided a typewritten transcription of the document in which the Hosty entry was omitted.
In 1964, the testimony of Shanklin and Hosty was undermined when another Dallas FBI field agent, Will Hayden Griffin, claimed that Oswald was definitely an FBI informant.
The message that Oswald handed in to the FBI office in Dallas remained a secret until 1975. It became public knowledge when someone in the FBI tipped off a journalist about the existence of Oswald's letter. Oswald's relationship with James Hosty was explored by the Select Committee on Intelligence Activities and the Select Committee on Assassinations. Hosty admitted that he had misled the Warren Commission by not telling them about the existence of the letter from Oswald. Sanklin denied knowing about the letter but this evidence was contradicted by the testimony of Hosty and William Sullivan, the Assistant Director of the FBI.
Shanklin remained as special agent in charge of the Dallas Field Division until his retirement in 1975
J. Gordon Shanklin died in 1998.