Hi, I would appreciate any advice you can give. I am debating whether or not to take a lifestyle poly. How far back to they go with questions about drug use and what is acceptable? Can these results be provided to other agencies?
In the case of the FBI, the drug questions cover your entire life. I think (but don't have direct knowledge) that it is the same with all federal agencies that polygraph applicants. The FBI will accept applicants who have used marijuana no more than 15 times. Any use of "hard drugs" is an immediate disqualifier.
Intelligence agencies like the CIA and NSA are more lenient with regard to past drug use, but they don't publish a cut-off standard.
The results of any federal polygraph examination to which submit may be provided to other (federal) agencies.
I cannot tell you whether or not to submit to a polygraph examination, but I suggest that you make an informed decision about it. See Chapter 3 of The Lie Behind the Lie Detector (http://antipolygraph.org/lie-behind-the-lie-detector.pdf) for an explanation of what to expect.