Not everybody dreams of being a drug addict but sometimes it happens and it goes without saying that many people who are behind bars are addicted. Besides the addiction issue, those who are in prison are most likely to be struggling with something. Spending days and nights locked in a cage is not fun at all and when there are free citizens to show these people that they matter to the society and the world at large then it will be easy to rehabilitate them. Many of those who are incarcerated spend time with are other inmates who may not be the most positive people in the world. Pen pals provide a channel through with those who are free and can help the prisoners not lose hope . It is not a surprise for the inmates to be eager to ask if you can help them with money, send them gifts or even get legal help for them but this should not be what you sign up for, given that even the prison system prohibits such. Your main goal should be to develop a friendship with the particular inmate which can be a channel for providing hope.
If you do not feel safe writing to an inmate alone, you can do so as a group. There are community and church projects in which members can write to inmates and the project leaders oversee the correspondences. Before you decide to forge a pen pal relationship with a particular inmate, make sure you have full disclosure of the crime they committed so that you do not have to battle your own feelings later. Do not be quick to judge people though because you may never know when your kindness and help will help someone to change for the better. Whatever you do, you should not be friends with criminals who are dangerous and have no regret for the pain and suffering they cause to the society.
It is one thing to be pen pal friends with an inmate and it is a totally different one to be attached to them. It is not your responsibility to fix what is broken with the inmates you become pen pal friends with because they have therapists for that and you may not be emotionally built to withstand what they are going through. When you find yourself losing grip on the purpose of the friendship, it is time you sought help from a therapist or a support group. However, note that not all inmates are dangerous and some are really committed to paying their dues and making changes and the best you can do to them is show support rather than shunning them.