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Forensic Psychology: Is there a link between mental illness and crime?

forensic psychology mental illness crime

Hello everyone, I hope that you're all having a great week.

Today's post is on Forensic Psychology and specifically the perceived link between mental illness and crime.

Please note that the psychology blog post below is a work-in-progress chapter from my forensic psychology book that I'm aiming to publish on the 17th February 2020 so this chapter is bound to change.

Extract from my Forensic Psychology book: (Work in Progress)

Mental illness and crime is a very interesting topic because if you watch the media or TV programmes then they always mention mental illness is related to crime.

But what is the truth?

That is the aim of this chapter as we scratch the surface of this modern topic.

Overall, there seems to be little doubt that certain types of mental disorders do in fact increase the likelihood of violence.

However, it is difficult to say who is at risk and who amongst the mentally ill are likely to be the most violent.

We’ll explore the reason why in a moment, but this is because other factors can increase the likelihood of violence as well as the mental illness.

What other factors increase the likelihood of violence?

Several other factors in addition to the mental illness itself tend to have a greater effect on the mentally ill. Including substance abuse and alcohol.

Although, this is because there’s fewer of them.

Putting this fact into an easy to understand example, let’s say that 100,000 clinically normal people were tested and 30,000 of them were discovered to be substance abusers.

That means that 30% of those people were substance abusers.

Subsequently, let’s say that 50,000 mentally ill people were tested; so there are 50,000 LESS people in this group, and the study found that 30,000 people in this group were substance abusers.

Meaning that 60% of this fictional mentally ill group were substance abusers.

Overall, showing you that merely as a result of there being less mentally ill people in the world. People can make grand claims that certain things affect the mentally ill more than clinically normal.

This highlights the need for good research to prove that these claims are based on facts and not unfair prejudice.

What is the relationship between mental illness and crime?

In reality, the relationship between crime as well as mental illness is small and in general, the public is more at risk from young men and substance abusers than the much rare schizophrenics.

Why is there is link associating mental illness with crime?

Personally, I blame the media and television because the media always focuses on the most sensational of crime (as discussed previously) and sometimes these are linked to mental health.

Nonetheless, this is a difficult question to answer so let’s explore in this topic further.

Firstly, it is too reductionist; where you try to narrow the reason down to one singular cause like stating depression is caused by genetics. Whilst ignoring the cognitive and sociocultural reasons. See Abnormal Psychology for more information; to say that mental illness causes crime.

Especially, when other factors are involved. Such as drugs used to treat the mentally ill can cause an increase in aggression.

Leading to a possible increase in violent crime and this wouldn’t be the fault of the mentally ill. As the fault would lie in the drugs as they caused the aggression to increase.

Furthermore, it could be society’s fault that a link is perceived to exist.

As changes in social policy; a governmental policy that affects people; can possibly lead to an increase in these perceived relationships.

For example: if there’s a change in social policy that states that community-based rehabilitation is better. Leading to the mentally ill are out of prison then this could increase the risk to the public as there could be more opportunity for the mentally ill to commit crimes.

Although, it MUST be noted that society has an amazing ability to generalise the actions of a few to an entire subgroup of individuals.

Thus, it is not a strange or unreasonable idea to propose that humanity stereotypes the mentally ill as criminals just because a hand of mentally ill people in the past have committed crimes.

This stereotyping; which can be read in more detail in my book Sociocultural Psychology; isn’t new as the following are all examples of where humanity has stereotyped others due to the actions of a few:

· All Muslims are terrorists due to the actions of a few extremists.

· All rapists are homosexual when it’s very few and in fact, more heterosexuals are rapists, as previously discussed.

· And there are many more examples.

Overall, this shows you how stereotyping can be applied to minorities by the dreadful actions of a few misguided souls.

Please note rehabilitation in the community is still important in the treatment of offenders.

In addition, the risk factors that can predict violent behaviour is becoming increasingly understood.

For example, as well as the types of diagnosis, whether the anti-social behaviour started in childhood or later, hallucinations or delusions can all predict violence.

Mental Illness and Courts:

Now it’s time to enter an interesting topic as I think one of the many reasons why mental illness, as well as crime, is associated together is because of the perceived overuse of the insanity defence.

For instance, I once remember that my mother mentioned that mental illness is rubbish because it’s always what criminals try and use to defend themselves.

Now, this… misguided opinion can be broken down into a few different components that reveal more about the general human population.

Firstly, people believe that the insanity or another mental illness defence is used a lot more than it actually is as it’s only used when there’s probable cause or when certain legal criteria are met.

One possible reason for this could be because humans have another great ability to only memory interesting pieces of information.

Therefore, people are more likely to remember a murder case involving an insanity defence as that isn’t the every day compared to your standard boring murder with a clinically normal person.

Secondly and this fact I find truly heart-breaking as a person who wants to support the mentally ill now and, in the future, but when a false claim is made about mental illness causing the crime and the offender doesn’t have a mental illness. This casts down on all the real cases were mental illness can legitimately be used as a defence.

I know that that was confusing, so I’ll take the same concept and put it in a different context.

Let’s use rape as an example.

Sadly, some people lie about being raped for various reasons and when the lie is discovered. This ultimately impacts the public’s confidence so when someone who has been raped comes along.

The public automatically think have they been rape or are they just trying to get attention like X was?

Meaning that society is more suspicion and most probably less likely to prosecute or take this real case seriously. As a result of one person’s lies.

Overall, I hope that this shows you how lying about having a mental illness can impact the Criminal Justice System.

The Psychology of Mental Illness and Courts:

Diving into the theory behind this new topic mental illness plays a massive role in courts as legal concepts. Such as competence, fitness to stand trial and diminished responsible have been around for centuries.

However, the problem with these mental legal concepts is that they are not simple to equate with the psychological variables as well as there aren’t the same in different jurisdictions.

In other words, it’s difficult to make an internationally recognised definition of these difficult legal concepts as each country has its own definition.

For instance: in the UK the considerations involved in fitness to stand trial involves:

· Having the ability to understand the evidence

· The ability to follow court proceedings

· Being able to understand that jurors can be objected and challenged

· The ability to instruct lawyers effectively

· Being able to understand the implication and meaning of the charges against them. (Grubin, 1996a)

Whereas, the US system can be simplified defined as the ability to understand and consult with a lawyer at that moment.

On the whole, I hope that you have found this interesting and enlightening.

I hope that you enjoyed this blog post and please feel free to leave a comment below.

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Have a great week everyone!

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