The Death Penalty Information Center, a Washington-based nonprofit organization, said statistics point to a continued record decline in the use of killing as punishment.
"America is in the midst of a major climate change concerning capital punishment," said Robert Dunham, DPIC's executive director and the author of the report.
"Whether it's concerns about innocence, costs, and discrimination, availability of life without parole as a safe alternative, or the questionable way in which states are attempting to carry out executions, the public grows increasingly uncomfortable with the death penalty each year."
That would be a steep 37 percent drop even from 2015, when 49 death sentences marked a 40-year low.
More From This Section
Executions declined to 20 this year, the lowest number since 1991 and well below the 1999 peak of 98 executions, stoking hopes for opponents of the death penalty.
The 2016 executions would be the fewest since 1972, when the US Supreme Court declared capital punishment unconstitutional. It reinstated the death penalty four years later.
Still, the possibility that the Supreme Court will once again outlaw the death penalty faded after Republican Donald Trump was elected president last month.
Trump, who takes office on January 20, is expected to fill the vacant seat on the nine-seat Supreme Court with a conservative judge, tipping the court to a conservative majority.