How long did the establishment of the secret investigative unit remain undisclosed to the public?

The correct answer is 35 years, indicating that the existence of the secret investigative unit was kept confidential for an extended period. This lengthy duration reflects a common practice in sensitive investigations where operational details are withheld to protect the integrity of ongoing or future work, ensure the safety of personnel involved, and maintain the effectiveness of undercover operations.

Maintaining such secrecy for decades can also stem from the need to avoid public scrutiny that might affect law enforcement practices or to prevent any potential backlash due to the nature of the operations being conducted. In the context of criminal investigations, this prolonged confidentiality can be essential for preserving the methods and resources used to combat serious criminal activities, allowing law enforcement agencies to operate without external interference or pressure. The length of time associated with this secrecy emphasizes the importance placed on operational security in criminal investigations.