1. There are many levels to having a security clearance.
2. Having clearance does not automatically grant access to classified information as a result of position, rank or title.
3. Having any level of security clearance also includes a required signature on a non-disclosure agreement.
4. Based on information, job duty or other stipulations, clearance has limitations including a ‘need to know’ basis.
5. Clearance can be and is in many cases a temporary condition for people in and outside of government.
6. Former DNI, James Clapper made the last and most recent modifications to security clearance access in January of 2017 at the behest of former President Obama. It is 27 pages and can be read here.
7. All people with any type or level of security clearance includes ‘public trust’.
8. There is an outside/contracted agency that performs the investigation of personnel applying for clearance.

Eligibility for access to classified information, commonly known as a security clearance, is granted only to those for whom an appropriate personnel security background investigation has been completed. It must be determined that the individual’s personal and professional history indicates loyalty to the United States, strength of character, trustworthiness, honesty, reliability, discretion, and sound judgment, as well as freedom from conflicting allegiances and the potential for coercion, and a willingness and ability to abide by regulations governing the use, handling, and protection of classified information. A determination of eligibility for access to such information is a discretionary security decision based on judgments by appropriately trained adjudicative personnel. Eligibility will be granted only where facts and circumstances indicate access to classified information is clearly consistent with the national security interests of the United States. Access to classified information will be terminated when an individual no longer has need for access.

Security clearances are subject to periodic re-investigation every 5 years. The individual will submit an updated security package and another background investigation will be conducted. The investigation will again cover key aspects of the individual’s life, but will start from one’s previous background investigation.