In 1992, the Dallas Morning News concluded that a death penalty case costs an average of $2.3 million, about three times the cost of imprisoning someone in a single cell at the highest security level for 40 years.

Excerpt from Testimony of Richard C. Dieter, Executive Director, Death Penalty Information Center, regarding the costs of the death penalty before the Colorado Senate Judiciary Committee. (February 7, 2007)

Death penalty cases are clearly more expensive at every stage of the judicial
process than similar non-death cases. Everything that is needed for an ordinary trial is
needed for a death penalty case, only more so:

• more pre-trial time will be needed to prepare: cases typically take a year to come
to trial
• more pre-trial motions will be filed and answered
• more experts will be hired
• twice as many attorneys will be appointed for the defense, and a comparable
team for the prosecution
• jurors will have to be individually quizzed on their views about the death
penalty, and they are more likely to be sequestered
• two trials instead of one will be conducted: one for guilt and one for punishment
• the trial will be longer: a cost study at Duke University estimated that death
penalty trials take 3 to 5 times longer than typical murder trials
• and then will come a series of appeals during which the inmates are held in the
high security of death row.

These individual expenses result in a substantial net cost to the taxpayer to
maintain a death penalty system as compared to a system with a life sentence as the
most severe punishment. It is certainly true that after an execution the death row
inmate no longer has to be incarcerated while the life-sentence prisoner remains under
state care. But that partial saving is overwhelmed by the earlier death penalty costs,
especially because relatively few cases result in an execution, and, even those that do
occur, happen many years after the sentence is pronounced. A study at Columbia
University Law School demonstrated how few capital cases actually result in an
execution: the study found that 68% of death penalty sentences or convictions are
overturned on appeal. The serious errors that are discovered require that at least the
sentencing phase be done over. When these death penalty cases are re-tried,
approximately 82% result in a life sentence. Thus, the typical death penalty case has all
the expenses of its early stages and appeal; it is then overturned, and a life sentence is
imposed, resulting in all the costs of a lifetime of incarceration. Nationally, only about
12% of people who have been sentenced to death have been executed.