Both state and federal prisons are meant to house and handle inmates convicted of severe crimes such as felonies. They may also be relocated from one state prison to another due to overcrowding or other reasons. Usually, inmates aren’t sent to state prison until they are sentenced. People who are sentenced to over twelve months will likely be sent to state prison. In the event they have sentenced to less than a year they will in all probability stay at the county jail for the remainder of their time. Pretty much all inmates start at the local jail after arrest and while awaiting their trial. What is the biggest distinction between a county jail and a state prison? The main distinctions are going to be the duration of stay and how serious the offense was. Rhode Island Jail Vs RIDOC Inmate Search.