Possession of a controlled substance occurs when any type of controlled substance is found on your person, in your residence or in your vehicle or any other type of property or location, or if you were in this area at the time of the discovery. The controlled substance may be an illegal drug such as cocaine, marijuana or heroin or it can be a prescription medication if the prescription is not in your name. Carrying a friend's prescription narcotics may result in possession of a controlled substance charge. It is important to keep in mind that if you are in a vehicle, a house or a boat where a controlled substance is found you may be charged, even if the drugs where not yours. You do not have to be aware that they are in the vehicle, house or other location to be considered in the charges. In some states possessing any type of drug paraphernalia used to inject, inhale or consume a controlled substance may also fall under this charge. Sentencing for possession of a controlled substance can range from probation and drug awareness programs through to jail time, especially if the prosecutor can prove intent to sell or distribute.