Homeless, bewildered, miserable, addicted and sometimes violent: The ranks of the mentally ill are swelling, and many New Yorkers come face to face with the crisis on a daily basis. Behind it lie policy failures half a century in the making.

Prior to the 1950s, our public mental-health system was composed almost exclusively of massive psychiatric institutions run by state governments. The facilities were often overcrowded, and the patients neglected and abused, which led to that approach being phased out beginning in the 1970s.

In its place came outpatient-oriented mental-health care, the model we’re familiar with today; only a very few traditional psych institutions were left standing.

The shift is often referred to as “deinstitutionalization.” Most New Yorkers are familiar with this history. What’s less known is that deinstitutionalization continues to this day.

Under the “Transformation Plan” for New York state’s Office of Mental Health, Gov. Andrew Cuomo’s administration has cut the number of patients admitted as well as the overall bed count in what remains of the state’s traditional network of institutions. The aim is the same as it has been since deinstitutionalization began: humane care at lower cost delivered on an outpatient basis.

And the results have also been the same. Deinstitutionalization bears much of the blame for the homelessness crisis and the high rate of serious mental illness among our incarcerated population. Both of those problems have been growing during the state’s recent reduction in beds.

We’re committing fewer mentally ill New Yorkers to state psychiatric institutions than we were five years ago. At the same time, we’re seeing more mentally ill wind up homeless or behind bars, leading to a greater strain on city services.

State psychiatric centers in New York City lost about 15 percent of their total adult bed capacity from 2014 to 2018, while the average daily patient-admission count dropped by about 12 percent.

From 2015 to 2017, the number of seriously mentally ill homeless in the city increased by about 2,200, or over 20 percent. In response, city government opened six new dedicated homeless shelters for the mentally ill.

Mental-health shelters, which house and treat clients, now stand as one of the largest components of the public mental-health system in the city.

Their total bed count exceeds the combined number of adult beds in state psychiatric centers in the city and adult psychiatric care beds in the NYC Health + Hospitals network.

Untreated mental illness also continues to press the city’s criminal-justice system, with fatal consequences. David Felix, Deborah Danner and Saheed Vassell were three mentally ill individuals who died in violent altercations with the police in recent years. And four NYPD officers have been killed by mentally ill perpetrators since 2014.

The number of “emotionally disturbed person” calls to the NYPD has risen every year since 2014. There are more seriously mentally ill inmates in city jails than there were in 2014. Rikers Island is host to a far larger population of seriously mentally ill individuals than any mental hospital in the city or state.

In designing the “Transformation Plan,” state policy makers were aware of the many failures that mar the history of deinstitutionalization, which is why they have increased investment in community mental-health services.

These services aren’t without benefits. Supportive housing programs and the like, for example, can reduce pressure on the inpatient mental-health system. But while more money for outpatient forms of care is necessary, it isn’t sufficient.

The “hardest cases” aren’t going to pursue community treatment, and for them it makes more sense to expand access to inpatient forms of care instead of cutting back.

The recent reductions are small relative to the cope of deinstitutionalization in New York, which saw the loss of tens of thousands of beds and over 90 percent of the original capacity. The city would still be dealing with untreated serious mental illness had the state’s bed count remained flat over the last five years.

We should question, though, the prudence of deeper cuts to inpatient mental health care at a time when untreated serious mental illness is plainly not under control. Many politicians accept the idea that New York has a long way to go on mental health care. Yet they insist the status quo is moving in the right direction. Evidence isn’t on their side.

Stephen Eide is a senior fellow at the Manhattan Institute.