The Death Penalty Information Center, a nonprofit organization that opposes executions and tracks the issue, also said the number of new death sentences was near its lowest level since capital punishment was reinstated in the 1970s. There have been 80 new death sentences so far this year, three more than in 2012 and down from 315 in 1996, the group said.
The 39 executions were carried out in nine states. Texas had the most, 16, followed by Florida, which had seven. Oklahoma had six, Ohio three, Arizona and Missouri two each, and Alabama, Georgia and Virginia, one each.
Texas, the leader in executions, illustrates the downward trend. It recorded 48 death sentences in 1999. This year, it was nine, marking the sixth year in a row that Texas had less than 10 death sentences.
Maryland abolished the death penalty this year, the 18th state to do so and the sixth in the last six years.
"I think the decline begins with the revelations about mistakes in capital cases - that innocent people could get the penalty and almost be executed has shocked the public to the point where death sentences are harder to obtain," said Richard Dieter, executive director of the center.
"There's a healthy skepticism about imposing a death sentence knowing that new information is almost certain to arise 10 or more years later," Dieter added. "Prosecutors are seeking the death penalty less, juries are imposing it less and ultimately executions are occurring less frequently."
One explanation for the relatively low level of executions is that many drugs used in lethal injections are manufactured in Europe, where some governments opposing capital punishment have banned exporting drugs for executions.
Leading up to Maryland's decision to abolish capital punishment was the discovery that authorities had convicted and sentenced to death the wrong man in the assault and murder of a 9-year-old girl in Baltimore County. DNA testing not only excluded Kirk Bloodsworth as the killer, but identified the actual perpetrator who is now in prison. Bloodsworth was with the Maryland governor when the measure abolishing the state's death penalty was signed into law. Bloodsworth was the first man exonerated from death row by DNA evidence.
In April of this year, the number of people on death row declined to 3,108 inmates, compared to 3,170 at the same time last year. The death row population has decreased each year since 2001. In 2000, 3,670 inmates were awaiting execution.
Take ABC13 with you!
Download our free apps for iPhone, iPad, and Android devices