The highest court in Connecticut overturned the death penalty as unconstitutional on Thursday, saving 11 prisoners on death row from execution in the northeastern US state.
Connecticut abolished capital punishment in 2012 for future crimes, but repeals were not retroactive, meaning that prisoners on death row for pre-existing convictions remained there.
The Connecticut Supreme Court issued the 92-page ruling in response to an appeal from convicted murderer Eduardo Santiago, who was sentenced to death by lethal injection in 2005.
"We are persuaded that... this state's death penalty no longer comports with contemporary standards of decency and no longer serves any legitimate penological purpose," it said.
"For these reasons, execution of those offenders who committed capital felonies prior to April 25, 2012, would violate the state constitutional prohibition against cruel and unusual punishment."
Santiago was convicted over a murder-for-hire scheme in which he shot a sleeping man in the head in December 2000 in exchange for a broken snowmobile.
The court noted "it no longer makes sense to maintain the costly and unsatisfying charade of a capital punishment scheme in which no one ever receives the ultimate punishment."
It referenced the state's "long, troubled history" with capital punishment, the "freakishness" with which the sentence is imposed but rarely carried out, and "racial, ethnic and socio-economic biases" in any death penalty system.
"We hold that capital punishment, as currently applied, violates the constitution of Connecticut," the court ruled.
The Death Penalty Information Center says there are 11 men on death row in Connecticut.
The state reenacted the death penalty by lethal injection in 1973, after which its first execution was in 2005.
There are 31 states with the death penalty in America, although 10 have renounced putting convicts to death, meaning that in practice 29 of the 50 states no longer use capital punishment.