The soaring crime rate has led to the proposal that criminals should be sentenced to longer periods in prison. Keeping the offenders in prison may help to prevent crimes from happening to some extent. If the penalties for crimes were not harsh enough, we would have a high rate of criminals repeating their acts. It is mainly through jail time that the offenders are forced to think about their unlawful acts and then become law-abiding citizens again. In this sense, prisons may help to make criminals less dangerous. However, concerns about the possible harm caused by lengthy jail terms are not unfounded. Severe punishments might ruin offenders' future, both physically and psychologically. For instance, there may a high chance that first-time offenders and those who are charged with a minor crime will be abused by felons who have been in jail for a long time, which may make these victims even more violent than before when they are released from prison. What is also needed therefor is treatment that helps criminals recover and function better in society. A more effective prison system should be established to reform criminals by providing them with job training and counseling. So, my conclusion is that a certain degree of restriction of criminals freedom is an efficient method to change them. But to make sure that they can be changed in a positive way, a longer time in prison is not necessarily the right way and it is rarely the only way.