How can you tell if your loved one is mentally ill and needs therapy?

Drug use is often a sign of deeper emotional distress that can be classified as mental illness. How can you tell if your loved one is mentally ill and needs therapy? Many who self medicate through drugs iare seeking a way to cope with chronic stress. Is counseling and therapy really the answer for those who are locked up in prison on drug charges?  A counselor and therapist discusses mental illness and how many labeled as "criminal" may receive the help they really need.