- Defining mental illness so broadly it includes up to 50% of the population
- Including only the most serious acts of violence (homicide) and excluding knifings etc.
- Excluding suicide or self-harm
- Excluding the most seriously ill patients in jails, prisons, shelters, psychiatric hospitals, from the population being studied
- Including only patients who are receiving treatment and excluding those who are not.
- Excluding mentally ill who also abuse substances
By using these tricks one can draw the conclusion that persons with mental illness are no more violent than others.
However, using some of the same tricks--which basically exclude the most seriously ill and only include the highest functioning-- should also show that that group is also no more likely to be victims.
So I looked into it just a little bit. It needs more investigating, but what I think is happening is that
those who claim persons with 'mental illness are more likely to be victims than perpetrators' are touting statistics that only work when you compare victimization rates among seriously mentally ill to violence rates in all mentally ill. Apples and oranges.The statistics that they use to calculate violence rates are artificially low, because they are from studies of 'all' mentally ill (25-40% of population) and narrowly define violence. The statistics that show victimization are artificially high because they only include studies of the most seriously ill (5-9% of population) and include suicide (which is often excluded from violence studies).
those who claim persons with 'mental illness are more likely to be victims than perpetrators' are touting statistics that only work when you compare victimization rates among seriously mentally ill to violence rates in all mentally ill. Apples and oranges.The statistics that they use to calculate violence rates are artificially low, because they are from studies of 'all' mentally ill (25-40% of population) and narrowly define violence. The statistics that show victimization are artificially high because they only include studies of the most seriously ill (5-9% of population) and include suicide (which is often excluded from violence studies).
I believe :
- If studies of the 25-40% of all persons with any mental illness were compared to the general population, the rates of both violence and victimization would be roughly the same in both groups. If suicide is defined as violence, it is possible that the rates of violence among all mentally ill would be higher than the general population since conservatively, 80% of 35,000 US suicides (28,000) are in people with a mental illness.
- If studies of the 5-9% who are seriously mentally ill were compared to the general population then rates of both violence and perpetration of violence would be significantly higher in the seriously mentally ill group. This would be true with or without the inclusion of suicide, but would be much higher if suicide was considered an act of violence.
I do not know if the ratio of victimization to violence among (i) people with serious mental illness or (ii) among people with any mental illness is different than the ratio of victimization to violence among the general population. And when answering that question, it would be important to identify or eliminate multiple incidents of both violence and victimization by a single person, in order to understand incidence rates.
Does it matter?
The answer to the above questions may not have significant policy implications, except for the fact that they are being used by mental health advocates to impede implementation of programs that help the most seriously mentally ill. That is because the same treatments that reduce violence also reduce victimization. Take Assisted Outpatient Treatment (a/k/a "AOT"; "Laura's Law" in California; "Kendra's Law" in New York.) It is only available for the most seriously ill and only to the subset of most seriously ill who have previously become violent, incarcerated, or needlessly hospitalized. AOT allows courts to order these individuals to stay in treatment as a condition of living in the community. While the court order has an exceedingly weak enforcement mechanism, studies still show it reduces both victimization and perpetration and suicide.
Thoughts?
Thoughts?
