A security clearance may be revoked at any time. There are 13 guidelines that are common to all agencies of the federal government that are used to determine eligibility for a clearance and to determine if an existing clearance ought to be revoked. There is an appeals process which varies with the employment status of the individual.

The Defense Security Service has this to say about the process of using the 13 Adjudication Guidelines:

The adjudication process is the careful weighing of a number of variables known as the whole-person concept. All available, reliable information about the person, past and present, favorable and unfavorable, is considered in reaching a clearance determination.

Each Guideline is comprised of three parts: 1) the Concern, 2) Potentially Disqualifying Conditions, and, 3) Mitigating Factors.

1) The Concern is a simple statement that sets forth the concerns the security community has about each Adjudicative Guideline.

2) The Potentially Disqualifying Conditions are conditions that, if present in the applicant’s life, may potentially disqualify him or her for eligibility or access.

3) The Mitigating Factors are used by adjudicators to balance against the Potentially Disqualifying Conditions. The Mitigating Factors consist of conditions that, if present in the applicant’s life, may cancel or lessen the severity of the Potentially Disqualifying Conditions.

One of the best ways to understand the guidelines for revoking a security clearance is to understand the adjudicative criteria.

The process is governed by two executive orders. Executive Order 12968 and Executive Order 10865 establish the initial framework for security clearance investigations and revocations.