Encyclopedia of Psychology and Law

then makes a final summary risk rating of low, moder-

ate, or high risk for violencedepending on the number

of risk factors present; their relevance to the individual

case; and the degree of intervention, supervision, or risk

management that is estimated to be necessary to miti-

gate risk. The HCR–20, like other SPJ instruments, pro-

vides a greater emphasis on risk management and risk

reduction than do some actuarial approaches. It does

this through the inclusion of dynamic,or changeable,

risk factors (the C- and R-scale risk factors) and the rec-

ommendation that these be reevaluated at important

decision-making junctures or according to some regu-

lar schedule.

Precise numeric algorithms or cut scores are not

used for clinical decision making as they are in actu-

arial prediction methods because of the high likeli-

hood of instability of such algorithms across settings

and samples due to idiosyncracies (i.e., capitalization

on chance associations) in their derivation.

User qualifications include expertise in violence

and in mental health assessment. Common user groups

include psychologists, psychiatrists, social workers,

psychiatric nurses, and professionals in related fields.

Some items (mental illness) may require users to pos-

sess advanced degrees (Ph.D. or M.D.), although other

users can rate these under supervision or provisionally.

Evaluation Studies

Evaluation research primarily has focused on ques-

tions of interrater reliability and predictive validity of

either the HCR–20 risk factors (numeric scores) or

summary risk judgments. Studies of the risk factors

and numeric scores are important to determine

whether these can be rated reliably and whether, as

they are defined by the HCR–20, they relate to vio-

lence. Studies of the summary risk judgments are

important to test whether raters, on considering the

HCR–20 risk factors and structured decision-making

principles, are able to make reliable risk-relevant

judgments that also are predictive of violence.

There have been several dozen peer-reviewed pub-

lished evaluation studies on the HCR–20. These have

been conducted across numerous countries (Canada,

the United States, Sweden, the United Kingdom,

Germany, the Netherlands) and settings (forensic psy-

chiatric, civil psychiatric, prison). Although there is

the expected variability in the findings, most research

demonstrates acceptable interrater reliability of both

the risk factors and the final summary risk judgment.

Similarly, on average, the HCR–20 demonstrates

moderate to large effect sizes with violence. Studies

have shown that the HCR–20 summary risk ratings of

low, moderate, and high risk perform as well as, or

better than, numerical (actuarial) use of the HCR–20.

The HCR–20 has been translated into 15 lan-

guages. It currently is on Version 2, and Version 3 will

be published in 2008 or 2009.

Kevin S. Douglas

See also Risk Assessment Approaches; Violence Risk

Assessment

Further Readings

Douglas, K. S., & Kropp, P. R. (2002). A prevention-based

paradigm for violence risk assessment: Clinical and

research applications. Criminal Justice and Behavior, 29,

617–658.

Douglas, K. S., Ogloff, J. R. P., Nicholls, T. L., & Grant, I.

(1999). Assessing risk for violence among psychiatric

patients: The HCR–20 violence risk assessment scheme

and the Psychopathy Checklist: Screening Version. Journal

of Consulting and Clinical Psychology, 67,917–930.

Douglas, K. S., Webster, C. D., Hart, S. D., Eaves, D., &

Ogloff, J. R. P. (Eds.). (2001). HCR–20: Violence

risk management companion guide. Burnaby, BC,

Canada: Mental Health, Law, and Policy Institute, Simon

Fraser University and Department of Mental Health Law

& Policy, University of South Florida.

Doyle, M., & Dolan, M. (2006). Predicting community

violence from patients discharged from mental health

services. British Journal of Psychiatry, 189,520–526.

Webster, C. D., Douglas, K. S., Eaves, D., & Hart, S. D.

(1997). HCR–20: Assessing risk for violence(Version 2).

Burnaby, BC, Canada: Mental Health, Law, and Policy

Institute, Simon Fraser University.

HEARSAYTESTIMONY

The rules of evidence regarding the admissibility of

hearsay testimony are complex, but in general, the law

treats hearsay as inadmissible evidence. A number of

exceptions to this general rule exist, however, and psy-

chologists have conducted research to examine how

jurors evaluate and use hearsay testimony in their deci-

sion making. No simple conclusions can be drawn at

this point from the research literature owing to the large

354 ———Hearsay Testimony

H-Cutler (Encyc)-45463.qxd 11/18/2007 12:43 PM Page 354