The district court is required to instruct, per the defendants request, on the lesser offense of possession of methamphetamine to the charge of possession with intent to distribute when the evidence is such that a jury could rationally find the defendant guilty of the lesser offense but acquit him of the greater. In this case, the prosecutors only evidence was that appellant, detained at the border crossing, was found to have a package of 159 grams of methamphetamine in his pants pocket and the opinion of an expert that the methamphetamine was possessed with intent to distribute. Because a rational jury could have found that the possession was for personal use, it was error not to so instruct. The court also found that introduction of evidence of appellants silence when the border patrol agent found the methamphetamine in appellants pocket and asked him what it was, violated appellants Fifth Amendment right to remain silent. In view of the overwhelming evidence against appellant, however, the inclusion of the evidence as to appellant’s silence was harmless beyond a reasonable doubt.