See Chapter 8 (Use of the Polygraph in Security Clearance Investigations) of Seldon Cohen's Security Clearances and National Security Information: Law and Procedures. The section on "Use of the Polygraph by the Department of Defense" states in relevant part: "...no adverse action may be taken solely on the basis of a polygraph examination that indicates deception, except upon the written finding by the Secretary or Under Secretary of Defense, or a Secretary of one of the military departments, that the classified information in question is of such extreme sensitivity that access under the circumstances poses an unacceptable risk to the national security."

Background: I'm a reservist and hold a DoD SCI clearance.  In my civilian job, I'm a network engineer. I don't currently utilize the SCI in either my reserve or civilian job (but is required for me to maintain in the reserves).
Situation: I've been offered a job that requires a full-lifestyle poly from a higher agency.
Question/dilemma: What would happen should I fail the full-lifestyle poly? I'm guessing that I would lose any/all lower clearances but I haven't been able to find anything in writing that addresses such a scenario.  I don't think I would otherwise have a problem passing it but, from what I've heard from people that have taken it and from reading the stories on this website, it doesn't sound 100% objective and I'm not sure I'm willing to take the risk of 1) losing my clearance and 2) getting kicked out of the reserves (which I really enjoy). This prospective job is extremely enticing but certainly not worth the potential risk. Does anyone know anything about this? Has it ever happened to anyone? Are there any regs you can point me to? Thanks for your help!