Legal Question in Constitutional Law in Michigan

More than one person may be charged with possession or distribution of a controlled substance. "Could the visitor get charged" of course it is within the realm of possibility. The possession may be actual or constructive (sufficient degree of dominion or control of the area or the substance, proximity , etc.). These types of cases are fact specific. A loitering where drugs are kept or stored charge seems more appropriate given the limited facts you have provided. The "what if" nature of your question leads me to believe a police officer may be squeezing you for information. Bottom line, do not talk to the police. Contact my alternate number I would be more than happy to advise you on this matter.