Forensic Psychology For Dummies (22 page)

Chapter 3

Providing Expert Evidence: Forensic Psychology and the Law

In This Chapter

Discovering the differences between various legal systems

Getting to know what an ‘expert’ witness is

Looking at what an expert can’t do or say in court

Seeing the different legal situations forensic psychologists get into

Forensic psychology hooks inevitably into the legal process, not least when practitioners are called to give expert testimony in court cases. Therefore, to understand how the discipline works you have to understand the legal process and how expert evidence fits into it. In this chapter, I provide a basic summary of how the law works and some general differences in how it operates in various countries, which in turn affect how forensic psychology expert witnesses fulfil different roles in different courts. I also demonstrate what being an expert witness entails and the ways in which the forensic psychologist can contribute in and around the courts.

In some countries, especially in Eastern Europe and non-English speaking places, people with a medical training still dominate the process of giving psychological evidence. They may be psychiatrists or even general medical practitioners. The preference for people with medical training as experts on psychological matters, such as fitness to plead, rather than psychologists used to be true in the UK and US, but forensic psychologists have certainly found their way into the legal limelight in the US ever since the early 1960s and are ever more present these days in the UK, Australia and Canada.

Understanding That Legal Systems Vary Worldwide

The central message of this section is that each country (or sometimes part of a country) has a different way of doing the law. Well, you wouldn’t expect things to be otherwise, would you! After all, human beings invented legal systems and because their histories and cultures vary, inevitably their institutions vary too. These variations make different assumptions about human beings and incorporate different sorts of protections to make sure that justice is done.

Throughout this chapter (and book) I refer to
jurisdiction.
By this term, I mean an area in which a particular set of laws hold sway. The word can also mean the sorts of laws that an authority has the power to enforce.

To illustrate, the Federal Bureau of Investigation (FBI) in the US has jurisdiction only over crimes that occur on government property or across state lines, or nationwide crimes such as serial killing, unless other state or city jurisdictions call them in for advice. In the UK, the Scottish legal system is quite distinct from that in the rest of the UK. Scotland is a different jurisdiction.

Facing up to an opponent: The adversarial system

If you love Hollywood and TV court-case movies, you’re familiar with the idea of a courtroom. A judge sits up on a high chair, much like a throne, in the middle of the court. The accused stands on a boxed-in platform nearby, lower than the judge, witnesses stand or sit on the other side of the judge. Across the room are two rows of people, the
jury
, who listen to the trial as it progresses and eventually present their verdict.

This is typical of what are known as Crown Courts in England and Wales and Federal and State courts in the US. In fact the great majority of court cases in many countries take place without a jury in front of what are called Magistrates. Typically these are three people who act as judges but aren’t trained lawyers, assisted by a legal advisor. There are a number of other types of courts that occur in different places but this is not a book on the law, so I’ll stay with what happens in the Crown Courts with a jury because that is where the role of the psychological expert is clearest.

The legal process used in most courts in the UK, the US and most Anglo-Saxon countries is known as the
adversarial system,
because at its heart is the adversarial nature of the defence and prosecution sides, played out before a judge or magistrates, and sometimes a jury that watches as a series of witnesses are questioned.

Initially the
prosecution
brings forward its witnesses. The prosecution officially represents the state or country; in the UK this is the queen. So much so that the most experienced and senior prosecutors are known as Queen’s Counsel. This prosecuting barrister (known as the prosecution attorney in the US) first questions the witnesses called by the prosecution, during a process known in the UK and Australia as providing
evidence in chief.
The US tends to use more informal terminology. This questioning is to reveal the facts of the case as the prosecution would wish the court to see them.

Next, in the
cross-examination,
the defence barrister (defence attorney in the US) challenges the prosecution witnesses’ accounts. They may try to challenge the reliability of the witness or the clarity of what they have said as you’ll see in Chapter 11. Sometimes, subsequently, a barrister asks one of ‘his or her’ witnesses a few more questions for clarification in the light of what the person said during cross-examination. Then the defence witnesses are brought in, with the defence first questioning the witnesses to provide the facts as the defence would like to court to see the. The prosecution barrister follows with a cross-examination that again has the objective of undermining the defence witnesses’ account of the facts. After all the witnesses have been dealt with, the prosecution and defence summarise the evidence as they see it. Then the judge does an overall summing up emphasising the legal issues the jury needs to take into account. The jury is then hidden away to make a decision about innocence or guilt, and in some jurisdictions also to determine the sentence a person gets when convicted.

Don’t assume that the cut and thrust in the courtroom, so beloved of filmmakers, is typical of most court cases. In my experience they’re remarkably tedious, conducted in an extremely polite manner, going over minute detail interminably. Also, a lot happens outside the courtroom, or out of hearing of the jury.

Considerable debate takes place about what evidence can be presented, with the defence and prosecution bargaining over which witnesses can be called and what aspects of their evidence can be put before the jury.

In addition, reports are prepared for both the prosecution and the defence that provide background information. Many aspects of these reports may not find their way into court but barristers can draw on them to influence the case they make and how they make it.

In the adversarial system the only thing that counts as evidence is what’s revealed in court. Mounds of documents and reports may have been prepared in support of the case, but only what’s said in court in front of the jury can be taken into account.