Failing a CIA polygraph has the potential to affect your current security clearance. The agency that granted your security clearance (presumably DoD) will at some point -- if not immediately, then at the latest when your security clearance comes up for periodic review -- be made aware of your polygraph results. A security-clearance holder who has failed a polygraph given by another agency will probably be questioned about it by background investigators, and might be asked to submit to a lie detector test administered by one of its own polygraph operators.

With regard to your second question, not all positions that require a TS/SCI level clearance require a polygraph examination. But it is commonly required for CIA contracts.

Ethan,

I don't know the intricacies of how, under what circumstances, and to what extent the CIA shares applicant information with other federal agencies. But information sharing clearly takes place. Another participant on this forum has mentioned that the CIA disclosed his sexual history to another agency, despite assurances that all information provided in the polygraph suite would be kept confidential.

hey everyone, i'm just curious what a failed DoD poly will mean for my TS-SCI clearance that I currently hold in my current position?  I work for another agency that does not conduct poly examinations.  does anyone know if they actively "reach out" to the home agency to screw over the employee?  Alternatively, obviously that precludes you from getting a future job with an agency that requires a poly, but what about other agencies?  Those that require S or TS clearances, but do not do polys.   Would this have to be asked on the SF-86?  Do agencies that don't deal in polys even ask about such things?