Does US court system order EtG hair test for alcohol consumption during probation? I have been totally abstinent from alcohol in the last 4 weeks, but my PO has suspicion that I consume alcohol after a violation that was recorded in my car ignition interlock (smart start) recently, which I admitted was because of mouth wash. The only fear I have is if the PO requests a hair test for alcohol consumption that spans over 3 months since I have consumed alcohol occasionally (weekends) over the last few months, however been totally abstinent for a month now. Are these hair follicle tests accepted legally? What are the chances that I pass with the hair testing? I read a lot of papers on EtG hair testing, but I have not found a reliable source that explains if the test uses an average over the 90 days or detects any occasions when alcohol was consumed over the cut off limit. For example if the cut off value is 1 unit of alcohol a day, will it average out the total number of drinks over the entire period, or will it detect any occasions where 1 or more alcohols were consumed. Just to expand more, if someone were to drink 0.5 units of alcohol every day and pass the test since the cut off is at 1 unit/day, how would this be different from someone who were to drink 9 units of alcohol for 5 random days within the span of 3 months?

Could you please provide some details? I have been worried about my situation for sometime now. I do not want my probation to be violated at any means. I have also read that chlorine from pool water, intense shampooing, and hair bleach will reduce or eliminate EtG levels in the hair. Or do you think that I am worrying too much and the PO will just warn me this time, and at most just give me a urine test?

Thanks.