CJ 3400, Theories of Crime
Dr. Matt Robinson
Signs of neurological
dysfunction highest in repeat, violent offenders, study shows
A large percentage of
criminal offenders show signs of possible neurological dysfunction, "with
the highest percentage being found among repeat violent offenders,"
according to a recent study by Matthew Robinson and Tom Kelley.
The researchers asked
probation officers to randomly select several cases each, and grouped the
selected offenders into three categories: 19 repeat violent offenders, 19
repeat nonviolent offenders, and 18 first‑time offenders. The average age of the offenders was similar
in all categories. Each probation
officer was asked to assess the cases using the AKelley
Form,@ designed by one of the authors for use in detecting
warning signs of neurological dysfunction.
In making their evaluations, the probation officers screened all medical
and legal documents accessible to them, and interviewed the offenders when
possible.
Robinson and Kelley say that
an overwhelming percentage of offenders in all groups were substance abusers
and exhibited psychological abnormalities (e.g., learning disabilities,
attention deficits, memory problems, or behavior problems such as aggression or
insensitivity). Other signs and symptoms
of neurological dysfunction included:
abnormal
physical conditions such as poor
coordination, unusual appearance, and speech and vision problems, seen in 68%
of violent repeat offenders, 58% of nonviolent repeat offenders, and 44% of
first‑time offenders;
head injuries (58%, 26%, and 17% respectively);
persistent
physical conditions such as
headaches, seizures, hypoglycemia, or dizziness (53%, 42%, and 33%
respectively);
family abuse (53%, 26%, and 39% respectively);
parental drug
abuse (62%, 37%, and 39%
respectively).
In addition, they say, 42% of
repeat violent offenders showed evidence of exposure to environmental toxins
such as lead.
"With few
exceptions," the researchers say, "[our data demonstrate] that a
higher percentage of repeat violent offenders were characterized by cues of
neurological brain dysfunction than repeat nonviolent offenders and first‑time
offenders." The factors that most differentiated repeat violent
offenders from the other two groups, they say, were birth complications, family
abuse, head injury, parental drug use, abnormal interpersonal characteristics
such as aggression or lack of empathy, and substance abuse.
"Also," they say,
"both repeat violent and repeat nonviolent offenders can be
differentiated from first‑time offenders in terms of maternal drug use during
pregnancy," with 26% of repeat offenders but only 5% of first time
offenders having been exposed to drugs before birth. "This would
suggest," they say, "that among our sample of offenders, maternal
drug use during pregnancy would appear to be a risk factor for repeat
involvement in criminal activity, both violent and nonviolent in nature."
In addition to finding that
violent repeat offenders are more likely to suffer from neurological
dysfunction than nonviolent or first‑time offenders, the researchers found that
the violent, chronic criminals showed higher levels of dysfunction,
averaging significantly more symptoms per offender than did the other groups.
The researchers note that all
of the probation officers commented on the lack of medical data available to
them in making assessments of offenders' neurological status, and they
speculate that even higher levels of dysfunction probably existed among the
population they studied. Yet even given the paucity of data available, they
note, the number of offenders exhibiting evidence of probable neurological
dysfunction was extremely high.
Even more importantly,
Robinson and Kelley say, the study revealed that a high percentage of the
offenders they studied suffered at very early ages from correctable conditions
including toxic exposure, birth complications, poor diet, and medical problems.
"Any and all of these potential sources of neurological brain dysfunction
can be reduced or even eliminated," they say, "suggesting that repeat
offending and violent repeat offending behaviors which relate to these
conditions may also be reduced or prevented."
Source:
Robinson, Matthew B. and Tom
Kelley (2000). "The use of neurological cues by
probation officers to assess brain dysfunction in offenders." In Diana Fishbein (Ed.), The Science,
Treatment, and Prevention of Antisocial Behaviors: Applications to the Criminal
Justice System. Kingston, NJ: CRI.