I was not truthful about my past drug use in a job interview. Now I have a job offer and need to get a secret security clearance. What should I do?
I smoked weed five days a week for most of this year (from maybe January to halfway through August) before quitting and moving out of the college town. In the past couple years before that, I have a smattering of other drug uses (shrooms, coke, addy; 3-5 times each and in small quantities). I might be able to make a case that I was in a different situation then since I had become a member of a fairly drug laden crowd which I'm now completely disconnected from.
Two weeks ago, I went in for a job interview at a defense contractor and things went smoothly. Towards the end, the interviewer asked me if there was anything that would prevent me from getting a secret level security clearance and listed off a couple of things such as bankruptcy or a criminal record. I said no. After I said no, he made some joke about drugs and we laughed. I silently realized that my drug use might be an issue, something I hadn't thought about until that point. I'd previously figured they'd give a drug test, I'd pass, done deal. Last week, I got call from them saying they were going to be offering me a job.
I've been doing research on security clearances and realized that past drug use can definitely be grounds for clearance denial, but the details on how much use and how long you've been “clean” are fuzzy. I'm not sure if I should even be thinking about accepting their offer. I'm nervous about going for the clearance and ashamed that I ended up being dishonest to the interviewer (even though it was mostly accidental). As soon as he mentioned drugs, even though it wasn't a direct question, I should have piped up but I didn't and now here I am.
My main question:
How should I approach this? Should I call them up and say “I've made a mistake and was dishonest, take me or leave me”? Maybe it's not as bad as I think and they can still work with me. It would be a nice job if I get it. Or should I turn down the offer, give some vague reason, and make the problem go away? I don't need the money and have plenty of time to keep looking for other jobs. I'd still feel bad about the whole thing, but nobody would have to know.
The third possibility, which I've been rejecting as unethical, is not saying anything them, accepting the offer, and then acting surprised if my clearance ends up being denied.
What are the chances of me actually getting a security clearance given my habitual drug use until three months ago?