TL:DR
Instigative, protective, and preventative. In that order.
Reforms required:
Abolition of plea bargains. Because an investigation is an experiment and you don’t haggle over findings. At best you debate to arrive at consensus.
No parole or probation. Because either a person is sufficiently rehabilitated to reenter society or they are not. If a citizen’s rehabilitation is in question then examine them till it isn’t and act accordingly.
Abolition of prison in it’s current form. The entire prison budget and deployment should be converted into a layered system of job training, education, mental and physical healthcare, and research of every relevant type. A place where prisoners don’t serve a fixed sentence but rather are inducted into a program from which only healthy prepared citizens can “graduate.”
Prisons today serve as torture chambers to terrorize the public into obedience and to satisfy their collective sadistic whims using primarily the poor, the foreign, and the mentally ill as their victims.
Prison should resemble primarily a very comfortable example of a school combined with a mental hospital. Among the thousands of advantages to this approach is respect for the cliche “innocent until proven guilty.”
Indeed to test the veracity of the system innocent volunteers should be paid to enter as criminals to in a double blind fashion measure how accurate rehabilitation procedures are.
All employees of this system should be required to complete the program and the program should be available to any on request. The objective isn’t to separate and punish criminals but you understand and prevent crime, to rehabilitate and improve the lives of everyone involved to whatever degree is possible and to research and understand when and why it is not possible.
People beyond repair should be kept in comfortable humane isolation until they die of natural causes serving society as subjects of study to the end of preventing the formation or perpetuation of people like themselves in future.
Everything about modern prison and criminal justice is wrong or fraudulent. I’d say 90% of the people in charge of it are corrupt in some fashion either fiscally, politically, or ideologically. The CEO of the private prison, the senator that gerrymanders prisoners in his district and like to play “tough on crime”, the sadistic corrections or police officer that just wants people to hurt or control for pleasure… These are the real and common truths of our “justice” system.
See also: