Forensic Psychology For Dummies (10 page)

Overall, many experiments are rather artificial. They use students pretending in various ways, or people are shown videos rather than experiencing actual events directly. Attempts to repeat the results in real situations aren’t always successful.

Nonetheless, some of the basic issues, especially in the area of testimony have been opened up by using carefully controlled academic experiments.

Studying in the field

Studies carried out in real life situations are generally regarded as producing results that can be applied more readily to other real circumstances. The most common form of study is in evaluating the impact of a particular intervention, such as a treatment programme for alcoholics or a screening procedure for selecting prison staff. Ideally such studies also require careful comparisons, at least with what happened before the intervention, but preferably with other established procedures.

These studies can explore many related processes in large scale analyses such as, for example, when considering the impact on future criminality of different ways of dealing with criminals. The results from this specific research merge with more general areas of criminality. Psychologists expect to pay particular attention to making sure that like is compared with like and carrying out detailed analysis of who was being dealt with in each of the forms of treatment or punishment. Often the impact of any intervention with an offender depends more on the nature of the offender – his age or how deep he’s in a criminal culture – rather than exactly what punishment or treatment he gets.

Assessing and measuring

The focus on individuals and understanding their particular psychology is such a central aspect of forensic psychology that a great deal of research and practice revolves around assessing the characteristics of individuals. In Part III I go through some of the processes that are used to develop assessment instruments. For now, you just need to know that this measuring is far from a casual activity.

When forensic psychologists decide that measuring an aspect of a person is useful, they take care to define the aspect precisely. It may be sexual fantasies, psychopathy, malingering, suggestibility, general levels of deviance or a whole host of other crucial aspects that may be relevant to some area of how the judicial system deals with such people.

Having decided on what to examine, the psychologist then forms and tries out careful statements, possibly in a questionnaire to be answered, or guidance of what’s to be observed in an interview or information gathered from records about the person. In some cases, the respondent may be asked to perform tests, or physiological measurements may be made of the person under certain conditions. An example is measuring if a man gets an erection when viewing different forms of sexually explicit pictures as a way of finding out his sexual preferences.

After the procedure is developed, it’s tested in several ways with different samples of people so that the procedure can be effectively calibrated. Eventually, after a number of studies of the procedure in actual use, a court of law may accept it as providing a measure that can guide the court’s deliberations or as the basis for determining treatment regimes or parole.

The two key aspects of reliability and validity are required before the measurement instrument can be trusted. Psychological assessment measurements can’t be taken at face value and have to be demonstrated through research:

Reliability:
How consistently the procedure measures what it measures. For example, a measuring tape made out of elastic isn’t reliable because it gives a different length for the same object every time it’s used.

Validity:
How well the procedure measures what it claims to measure. A measure of sexual fantasies that was in fact assessing how much pornography a person watched can be misleading, although asking the person about what he liked watching may indicate sexual preferences.

Validity is more difficult to establish than reliability because validity requires a careful definition of what the measurement is supposed to be measuring.

There are lots of other aspects of psychological measurements that are important before they can be used with confidence, but two are enough for now. You can find out about other psychological measurements in Part III.

Studying individual cases

Many breakthroughs in medicine come from the study of an individual person. Working from a single case is much easier for doctors, because usually the majority of human bodies are more or less physically the same: two arms, two eyes, the same sort of kidneys and liver (give or take a few beers!).

In contrast, an individual’s psychological make-up is distinctly different from the next person’s, and even if many similarities exist, everybody
thinks
that they’re unique. For this reason, psychologists frown on a single study as a way of making discoveries and then applying the discovery to numberless people. However, single cases are very useful in illustrating results drawn from other scientific procedures, which is how I use case-studies throughout this book.

Getting theoretical

I don’t want you to think that forensic psychology is all numbers and observation and prisoners filling in questionnaires. None of these ways of collecting information about people makes much sense unless accompanied by explanation and understanding of what the forensic psychologist is doing. In science such insights come from what is broadly known as ‘theory’.

Psychological theories aren’t idle speculations or impossible suggestions in the way that the word theory is often used in daily life. In the study of psychology,
theories
consist of carefully defined ideas that are related to each other in an argument, which is then tested by obtaining some information (usually called data) from actual situations.

So, when you ask whether criminals are born or created by their experiences, called the ‘nature or nurture’ question, you’re really asking which of the two broad theories about the origins of crime is most plausible.

As I show throughout this book, when you start to define more clearly what key concepts mean and you look for the evidence, the theories usually become more subtle and more complicated. But that’s what makes forensic psychology so fascinating.

Professional ethics

All of the activities that forensic psychologists are engaged in carry serious consequences, both legally and professionally. A person’s life or freedom can hang on what the psychologist says. There are therefore many constraints and guidelines for what forensic psychologists do. I explore ten of these in Chapter 17.

Working with Others: People and Places That Forensic Psychologists Encounter

Forensic psychologists don’t spend their time locked in prison cells chatting to serial killers. They find themselves interacting with a great range of people in various ways:

Patients:
Some people are assigned to forensic psychologists through the legal process and offered therapy or given help in other ways to cope with any psychological problems.