Crime Library: Criminal Minds and Methods

The Art of Forensic Psychology


Matthew Shepard
Matthew Shepard

On October 7, 1998, Matthew Shepard, 21, was found badly bludgeoned and tied to a split-rail fence east of Laramie, Wyoming.  Despite emergency care, he died five days later and two young men were arrested for his assault and murder: Aaron McKinney, 22, Russell Henderson, 21.  Henderson accepted two life sentences for his testimony against McKinney.  He admitted that they had picked up Shepard with the intent to rob him, but McKinney had beaten him savagely and ordered Henderson to help tie him up.  McKinney's attorneys wanted to develop a case based on past traumatic homosexual episodes that had triggered rage against Shepard, but the court did not allow it.   McKinney was convicted of felony murder, i.e., murder that occurs in conjunction with another felony crime such as kidnapping or armed robbery.  He was eligible for the death penalty, and the prosecution was eager to press for that.  But during the sentencing phase, psychiatric testimony helped to persuade all of those involved not to pressure for the death penalty, including Shepard's parents.  Mental health professionals can often make a difference before the sentence is imposed.

The purpose of a sentence for a crime is four-fold:

  • retribution
  • deterrence
  • community protection
  • rehabilitation

The federal government, along with a number of states, has adopted determinate sentencing schemes to punish offenders equally, although this practice has come into question.  These courts rely on sentencing guidelines that offer a range of time periods for given crimes, e.g., from 10 to 20 years.  In non-death penalty cases in most jurisdictions, the judge determines the sentence, but the probation department prepares a pre-sentencing report with recommendations.  They use all relevant information from the prosecutor, defendant, victims, defendant's family and employer.  The defendant's attorney may suggest an appropriate sentence.

During this process, psychologists can make treatment suggestions, address the defendant's degree of culpability, and offer predictions about the future risk of re-offending.  When there is little latitude in the sentencing, the clinician's role is restricted, but they can still address mental impairment or duress that may influence a judge to accept a lower-end sentence recommendation.

Death penalty cases are divided into guilt phase and sentencing, or penalty.  During the penalty phase, evidence is offered for aggravating or mitigating factors.  A defense attorney may request a psychiatric assessment for the defendant, but a prosecutor may also do so as a way to strengthen the case against him or her.  Aggravating factors might include such behaviors as a long criminal history or evidence of torture during the commission of a crime.  Mitigating factors include childhood abuse, mental and neurological disorders, and distorted perception of danger.  A jury considers the evidence and makes a decision. 

In 1983, the Supreme Court has upheld the constitutionality of permitting the death sentence based on predictions of future violence.  In Barefoot v. Estelle such clinical testimony was allowed.  Thomas Barefoot had burned down a barn and then shot and killed a police officer.  He was convicted and subjected to a hearing for the death penalty.  The decision was to be partly based on whether the defendant posed a threat of future dangerousness, and the state had to prove it beyond a reasonable doubt.  The prosecution relied on the testimony of two psychiatrists who were given hypothetical situations to consider that were similar to the case and asked if the individual in the situation would probably commit future violent acts.  Both said yes.

Professional organizations protested the unreliability of such testimony, as well as of risk assessment in general based on such criteria, but the court cited precedents, and Barefoot's death sentence stood.  Since then, risk assessment has improved, and the predictions now utilize both clinical judgment and statistical data.  The best predictions, however, are for short-term threat assessment, qualified by the context and its potential for change. 

Once a person has been sentenced to prison, psychologists play yet another role.

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