Abnormal Psychology

Ethical and Legal Issues 731

To prevent such people from harming themselves or others, the law

provides that they can be confi ned as long as they (continue to) pose

a signifi cant danger.

When clinicians evaluate present and future dangerousness, they

base their judgment (in part) on an individual’s history of such be-

havior, but such information provides only limited guidance (Perlin,

2000c; Schopp & Quattrocchi, 1984). In fact, whether someone is

an imminent danger to self or others is often not clear. For example,

although the possible dangerous acts the person may commit should

be “imminent,” exactly how this word is defi ned remains unclear

(Meyer & Weaver, 2006).

Actual Dangerousness

Mentally ill individuals who engage in criminal acts receive a lot of

media attention, which may lead people to believe that criminal be-

havior by those with mental illnesses is more common than it really

is (Pescosolido et al., 1999). In fact, criminal behavior among the

mentally ill population is no more common than it is in the general

population (Fazel & Grann, 2006). However, two sets of circum-

stances related to mental illness do increase dangerousness: (1) when the mental

illness involves psychosis, and the person may be a danger to self as well as others

(Fazel & Grann, 2006; Steadman et al., 1998; Wallace, Mullen, & Burgess, 2004),

and especially (2) when serious mental illness is combined with substance abuse

(Maden et al., 2004). The relationship between various major mental illnesses, sub-

stance use disorders, and violence is shown in Figure 16.1.

It is worth stressing a cautionary note: Although in this section we have focused

on the relation between some forms of mental illness and violence, as occurred with

Goldstein, most mentally ill people are not violent. Indeed, if they are in jail or

prison, it is usually for minor nonviolent offenses related to either trying to survive

(e.g., stealing food) or to substance abuse—the mental illness is not a direct cause of

the incarceration (Hiday & Wales, 2003).

16.1 • Lifetime Prevalence of Violent Behavior

Substance use disorders (with or without a comorbid major

psychological disorder) are associated with a much higher

rate of violent behaviors (such as the use of a weapon in

a fi ght or coming to blows with another person) than is

observed in the general population (Swanson, 1994).

Source: Monahan et al., 1994. For more information see the Permissions

section.

Figure 16.1g

0

10

20

30

40

50

Prevalence of violence (percentage)

No major

psychological

disorder

Schizophrenia,

bipolar disorder,

or major

depressive

disorder

Substance

abuse or

dependence

only

Major

psychological

disorder and

substance abuse

Although some people with mental illness may

create a public nuisance, like this man yelling

at voices that only he can hear, such public dis-

plays are not dangerous and should not, in and

of themselves, lead to hospitalization (Perlin,

2000c).

Adam Sylvester/Photo Researchers, Inc.