Marijuana in the past and presentMarijuana is a mixture of leaves, stems and flowering tops of the Indian hemp plant Cannabis, it can be smoked or eaten for its hallucinogenic properties and pleasant effects. Marijuana has not been proven to be physically addictive, but psychological dependence can develop. Many users describe two stages of marijuana intoxication. During the first level the user will feel dizzy; subsequently the user will experience peace of mind. Mood changes are often accompanied by an altered perception of time. A person will think that hours have passed, but in reality only minutes have passed. The thinking process is usually interrupted by incongruous ideas, images, and memories. Many users report increased appetite, heightened sensory awareness, and various hallucinogenic pleasures. Negative side effects include confusion, panic, anxiety attacks, fear, feelings of helplessness and loss of self-control. Numerous successful efforts were made in the United States, especially in the 1970s, to reduce criminal penalties for marijuana possession and use, but many of the resulting laws have since been amended or repealed. Smoking marijuana is so taken for granted in much of our culture that many people today assume that a marijuana crime is unlikely to result in a prison sentence. The fact is that there are more people in prison today for violating marijuana laws than at any other time in the nation's history. Data provided by the U.S. Bureau of Prisons and the Sentencing Commission suggests that one in six inmates in the federal prison system have been locked up for a marijuana offense. The number of inmates currently held in state and local prisons is more difficult to estimate; an estimated guess would be another 20,000-30,000. A dozen or more marijuana offenders could now serve life sentences in federal penitentiaries without hope of parole. The number of prisoners sentenced to die in prison can reach hundreds if middle-aged prisoners with sentences of more than twenty years are included. Other inmates are serving life sentences in state prisons across the country for growing, selling or even possessing marijuana. Vigorous enforcement of marijuana laws has led to four million arrests since the early 1980s. Due to mandatory minimum sentences, many of those convicted are receiving stiff prison sentences; although violent criminals are released due to lack of space.