It is far less expensive to society to treat mental illness including drug-addiction up front as an outpatient than at the back end with payments to police, courts, prosecutors, public defenders, jails, prisons, parole agents, treatment for medical care caused by neglect, public aid for family members neglected by the mentally ill person, etc. Would you rather pay $40,000 a year to incarcerate someone PLUS all the above collateral costs or $10,000 per year to provide excellent mental health care as an outpatient? The answer is simple: A BIG YES! Our politicians are simply stupid.
This article says it all and provides links: http://www.washingtonpost.com/blogs/ezra-klein/post/does-cutting-mental-health-care-increase-the-prison-population/2011/06/02/AGzNdVHH_blog.html?wprss=ezra-klein