It’s an oft-repeated trope: You can’t help people with mental illness if you don’t do something about it.
But according to new research, it may not be true.
In a paper published this week in the journal PLOS One, researchers at the University of Pennsylvania looked at cases of violent crimes committed by mentally ill people in Philadelphia over a six-year period, and found that the cases weren’t actually linked to the diagnoses of their mental illness.
The study used data from the Philadelphia Department of Mental Health’s Behavioral Risk Factor Surveillance System, a statewide database of police and public health data.
It found that of the 521 cases of aggravated assault committed by persons with mental illnesses in Philadelphia between 2011 and 2015, only one involved a weapon.
That wasn’t a crime because it didn’t involve a weapon, the researchers noted.
The other 39 cases of physical assault were committed by the same individuals.
The authors wrote that “physical assault and aggravated assault are both a subset of other violent crimes, and thus represent a subset in the same population.”
The researchers also found that violent crime rates in Philadelphia had decreased since 2010, despite the fact that the number of mentally ill individuals in the city remained high.
In other words, it seems that the researchers missed a chance to find a correlation between the mentally ill being more violent than the rest of the city, and the increased crime rates that followed.
And this is the problem with this type of research: It doesn’t seem to make much sense.
“In my experience, if you can’t say something that’s consistent with the facts and your data, it doesn’t make any sense,” said Dr. Michael Siegel, an associate professor of psychiatry at the Johns Hopkins University School of Medicine who was not involved in the research.
Siegel, who is also a clinical professor of psychology at the university, told Polygon that his theory about why there’s a correlation was that the mentally sick are more likely to commit violent crimes because they are more dependent on substances like alcohol and drugs.
“So if you’re getting a lot of people who are addicted to those substances, you’re going to have a lot more violent offenders,” Siegel said.
“The other thing is that they are also more likely in this population to be homeless, and then they are going to be at greater risk for committing a crime.”
The findings of the Penn researchers, who looked at nearly 300,000 records of police, social workers, and health professionals in Philadelphia during the period, didn’t find a statistically significant increase in violent crime from 2011 to 2015, nor did the researchers find any correlation between mental illness and violent crime.
The Penn researchers also note that the data didn’t reflect the type of people involved in violent crimes.
The Philadelphia Police Department’s Behavioral Analysis Unit, which was responsible for collecting data on violent crime, was responsible only for reporting crimes that occurred on the police department’s property.
So the researchers did not examine whether the crimes were committed at places like the police station, in the parking lot, or in the backyard of the police officer’s home.
Sauer said the findings suggest that the mental health community needs to be careful not to link mental illness with violent crime because the data doesn’t reflect that fact.
“I think the data is pretty clear that violent crimes are increasing,” he said.
“So if we want to have this discussion about mental health, I think we have to be very careful about the fact the numbers don’t show anything.
It’s the data that’s missing.”
It’s not clear if the Philadelphia police department will make changes to its data collection and reporting practices.
“We’re not going to know how long the research will last, because we don’t have any sort of data that would show what was going on in the police departments,” Sauer said.
But the study has other important implications for people with serious mental illness, he added.
“If they can be counted as violent criminals, that’s an important message for the community.”
The research team found that “unintentional” or unintentional violent crimes accounted for more than 90 percent of the cases in Philadelphia that involved a mentally ill person.
But it’s possible that the study’s findings could have been a case of statistical error.
Sink said the research team did not have enough data to make a causal link between the number and the violent crime rate.
“There was a small study in New Zealand that looked at violent crime and mental illness,” Sink said.
He added that it is possible that this study may have missed a significant and statistically significant association between violent crime in Philadelphia and the number who had mental illness or mental illness history.
“It would be interesting to do a more extensive study, and see if it is statistically significant,” he added, noting that the city has seen a dramatic drop in violent violence in recent years.
“But I think that’s really what the research needs to look at and really understand the relationship between mental health and violence,”