Was the tragic incident at Virginia Tech the result of a failure of Virginia's mental health system? Slate recently posted Seung-Hui Cho's commitment papers and they are revealing: the magistrate who heard Cho's case determined that he was "an imminent danger to himself as a result of mental illness," but determined that there were "alternatives to involuntary hospitalization."

After the shooting, Sally Satel at AEI argued that Virginia needs to reexamine its involuntary treatment laws and adopt a lower threshold for commitment, more in line with states like Arkansas and Hawai'i. Others, like Brian Jenkins at RAND, contend that the tragedy probably could not have been prevented and might not have a solution.

It's impossible to make sense of the debate, though, without understanding the extent to which we've dismantled our mental health system in this country. Brick-by-brick, cell-by-cell, we deconstructed what was once a massive mental hospital complex and built in its place a huge prison.

The sheer magnitude of transformation is absolutely remarkable. It is visually shocking — especially given the exponential rise in incarceration in this country in the past thirty years. The following figure gives a snapshot. It shows the aggregate rate of institutionalization in the United States for the period 1934 to 2001, with disaggregated trend lines for mental hospitalization on the one hand and state and federal prisons on the other.

FIGURE: Rates of Institutionalization for Residents in All Mental Institutions and State and Federal Prisons in the United States (per 100,000 adults)

Although our current rates of imprisonment in state and federal prisons are extraordinarily high, the level of total institutionalization (in prisons and asylums) was higher during the 1940s and 50s.

We all know that prison populations skyrocketed nationwide beginning in 1970, rising from under 200,000 persons to more than 1.3 million in 2002. That year, in 2002, our prison rate exceeded for the first time the 600 mark (600 inmates per 100,000 adults) — by far the highest rate and raw number of incarcerated persons in the world.

But what is far less well known is that the United States as a whole institutionalized people at even higher rates in the 1940s and '50s. If you look at rates of persons in mental hospitals and prisons per 100,000 adults, in the period between 1935 and 1963 the United States consistently institutionalized at rates above 700 per 100,000 adults — with highs of 778 in 1939 and 786 in 1955.

In a recent study, I collected state-level data on mental hospitalization for the twentieth century, and my findings are staggering. For one thing, there was a wide range of institutions. In addition to state and county public mental hospitals, there were public and private institutions for "mental defectives and epileptics" and for "the mentally retarded," psychiatric wards in general and VA hospitals, "psychopathic hospitals," city hospitals, and private mental hospitals.

There was also an entire parole system for persons institutionalized in mental hospitals and the parole numbers were non-negligible: on December 31, 1933, for example, 46,071 mental patients were on parole or otherwise absent, representing almost 10 percent of the total institutionalized patient population of 435,571.

One of the most perplexing things I discovered is that there is a strong statistical relationship between aggregated institutionalization (in asylums and prisons) and serious violent crime. Using state-level panel regressions spanning the entire period from 1934 to 2001, including all 50 states, and controlling for economic, demographic, and criminal justice variables, I found a large, robust, and statistically significant relationship between aggregated institutionalization and homicide rates. The findings are not sensitive to weighting by population and hold under a number of permutations, including when I aggregate jail populations as well.

I say "perplexing" because the populations in asylums and prisons were very different: residents in mental hospitals were more white, female, and older than our current prison populations. In 1966, for example, there were 560,548 first-time admissions to mental hospitals, of which 310,810 (55.4%) were male and 249,738 (or 44.6%) were female. In contrast, new admittees to state and federal prison were consistently 95% male throughout the twentieth century. There were also sharp differences in racial and age compositions.

Because of these sharply different populations, it's not clear yet what to conclude from my study — and it's far too early to draw public policy implications. But a few things are clear.

The first is that we should not be surprised that there are so many persons with mental illness behind bars today. We deal with perceived deviance differently than we did in the past: instead of getting treatment, persons who are viewed as deviant or dangerous are going to jail rather than mental hospitals.

The second is that we should not be surprised that our mental health systems are in crisis today. The infrastructure is simply not there. This is evident in states across the country where persons with mental illness are being housed in jails rather than treatment facilities.

What is also clear is that Seung-Hui Cho probably would have been institutionalized in the 1940s or 50s and, as a result, the Virginia Tech tragedy may not have happened. According to the New York Times, the director of the campus counseling services at Virginia Tech said of Cho: "The mental health professionals were there to assess his safety, not particularly the safety of others." It's unlikely we would have taken that attitude fifty years ago.

But the problem is, we would also be institutionalizing another huge swath of humanity — and it's simply not clear how many of those other lives we would be irreparably harming in the process.

The classic texts of social theory from the 1960s — Erving Goffman on Asylums, Gerald Grob on The State and the Mentally Ill, David Rothman on The Discovery of the Asylum, Michel Foucault on Madness and Civilization, Thomas Szasz on The Myth of Mental Illness, Michael Ignatieff on A Just Measure of Pain, and many others — describe in chilling detail how closely mental institutions began to approximate the prison and the "total institution." These critical writings should remind us of the other price that society pays when we commit and institutionalize each other.