I strongly suggest that you hire an experienced federal criminal litigator. They would be in the best position to tell you re: the recidivist issue. Talking about this case any more on here could potentially jeopardize any possible defense you may have for that alleged offense of your "friend," and only by speaking confidentially with an attorney could you best discuss the facts of the case, not only the sentencing issue. Good luck.
A federal defendant is considered a Career Offender, pursuant to the United States Sentencing Guidelines (USSG Section 4B1.1), if he or she (1) is 18 years of age at the time the instant offense was committed; (2) the instant offense is a crime or violence or a controlled substance offense; and (3) the defendant has at least two prior felony convictions for a crime of violence or a controlled substance offense. However, the term "controlled substance offense" is defined in USSG Section 4B1.2 as one that prohibits the manufacture, import, export, distribution or dispensing of a controlled substance. There is no time limit on the age of the convictions that may be counted under the Career Offender provision; the time limitations that you reference pertain to the criminal history score in USSG Section 4A1.1 (which is the subject or another very long answer).
Joshua Sabert Lowther, Esq.
NATIONAL FEDERAL DEFENSE GROUP
The answer to your question is rather complicated. More information is needed. It sounds like each of your prior marijuana cases could be career offender predicates as drug offenses.
You are right that there are time limits. The provisions of §4A1.1(a), (b), or (c) govern whether or not your priors are counted. Even if you were not imprisoned initially, if you were revoked from supervision, at some point, your 1986 sentence could count as a predicate, if the sentence brings that case within the time limit.
The good news is that the career offender guideline, like all of the federal sentencing guidelines, is now advisory. The bad news is that the guidelines are advisory. So even if you are a career offender, the judge could give you a break and a sentence lower than the career guideline. On the other hand, even if you are not a career offender under the guidelines, a judge could decide that someone with a prior federal sentence and two other prior drug cases is in fact someone who made a living selling drugs as a career. The judge might decide that you deserve a higher than guideline sentence. It depends on the judge and all the other circumstances in the case.
You need an experienced federal defense lawyer.
My answer to your question is based on the facts that you provide in your question. Additional factual details about your situation could change my answer completely. The law in inherently uncertain and always subject to change.
You and your attorney need to sit down, carefully review your criminal history and compare it to the federal sentencing guideline manual. You also may have other concerns, including sentencing enhancement notice which could subject you to a life sentence.