future contributions of the defendant would be sacri-
ficed if he or she were to be sentenced to death.Legal Doctrines
Governing Capital Mitigation
The explicit use of mitigation as a key element in the
death-sentencing process was first acknowledged by
the U.S. Supreme Court in Gregg v. Georgia(1976)
and its companion cases. Here, the Court approved a
number of new state death-sentencing statutes that
had been enacted in response to the Court’s earlier
declaration in Furman v. Georgia (1972) that the
death penalty was unconstitutional as it was then
being applied in the United States. The Gregg opinion
endorsed a framework for capital sentencing that
appeared in several of the revised state death penalty
statutes that the Court reviewed and that was derived
from the American Law Institute’s Model Penal
Code(1962). The Model Penal Codeprovided a list
of mitigating and aggravating circumstances that it
suggested jurors should “take into account” in decid-
ing whether to impose a death sentence. The Court
endorsed this approach as an acceptable way to
attempt to guide the discretion of the jury.
Two years after Gregg, in Lockett v. Ohio(1978),
the Supreme Court provided an expansive interpreta-
tion of the scope of admissible capital mitigation,
indicating that the sentencer in a death penalty case (at
that time, either a judge or a jury) must “not be pre-
cluded from considering,” as mitigating factors, “any
aspects of a defendant’s character...that the defense
proffers as a basis for a sentence less than death.” In a
long line of cases that followed, the Court continued
to endorse the principle that capital defendants should
be permitted to introduce a very broad (indeed, seem-
ingly limitless) range of mitigating evidence. These
opinions repeatedly established the right to introduce
a wide range of mitigating evidence by declaring
unconstitutional any statutes, procedures, or rulings
that precluded or limited defendants from doing so.
However, the Court nonetheless failed to impose any
requirement, standard, or guideline governing whether
and when capital attorneys shouldintroduce mitigat-
ing testimony (or what remedy, if any, defendants
were entitled to if their attorneys failed to do so).
As a result, although defendants were entitled to pre-
sent virtually unlimited mitigating evidence, many
attorneys—because they lacked the training, experi-
ence, or resources—managed to present little or none
on their client’s behalf.Nearly 25 years after Greggwas decided, however,
the Court took steps to remedy this problem. Thus, in
Williams v. Taylor(2000), it reversed a death sentence
because a capital defense attorney had failed to inves-
tigate, assemble, and present important and available
mitigating evidence in a death penalty case. Specifi-
cally, the Court found that the defense attorney had
rendered “ineffective assistance of counsel” because
he had failed to “conduct a thorough investigation of
the defendant’s background.” As a result, he did not
uncover and introduce potentially important mitigating
evidence at trial, including the fact that the defendant
had endured a “nightmarish childhood,” had been
raised by criminally negligent and physically abusive
alcoholic parents, had been committed to an abusive
foster home, and was borderline mentally retarded.
The trial attorney also failed to introduce available evi-
dence about the defendant’s positive prison adjust-
ment, including his prior good behavior in prison and
extremely low violence potential in structured institu-
tional settings.
In several subsequent decisions, the Court reaf-
firmed the constitutional mandate that capital attorneys
must diligently pursue and present available mitigation
on behalf of their clients. In perhaps the most important
of these cases,Wiggins v. Smith(2003), the Court indi-
cated that defense attorneys must investigate, analyze,
and, where appropriate, present mitigating social his-
tory evidence. Wigginsemphasized that evidence of a
seriously troubled background is highly relevant to
what has been called “the assessment of a defendant’s
moral culpability” and acknowledged that when juries
are confronted with such evidence, they are likely to
return a sentence less than death. The Court concluded
that the American Bar Association Guidelines(2003)
for competent representation in capital cases help
establish “prevailing professional norms,” thereby mak-
ing it incumbent on defense attorneys to investigate,
analyze, and consider presenting “all reasonably avail-
able mitigating evidence,” including the defendant’s
“medical and educational history, employment and
training history, family and social history, prior adult
and juvenile correctional experience, and religious and
cultural influences.”Psychological Underpinning
of Capital Mitigation
The doctrine of mitigation is decidedly not a doctrine
of legal excuse. It allows jurors to acknowledge defen-
dants’ legal responsibility for their actions and to62 ———Capital MitigationC-Cutler (Encyc)-45463.qxd 11/18/2007 12:41 PM Page 62