WASHINGTON — Is the death penalty in America gradually dying?

There have been just two executions since May 1 and the total for 2016 probably will hit a 25-year low.

Execution drug shortages, sometimes grotesque errors in death chambers and legal challenges to sentences imposed by judges have contributed to a dramatic decline in the number of states that are carrying out executions.

Just three states, Texas, Georgia and Missouri, are using the death penalty with any regularity, though Texas has not executed anyone since April. Four executions are scheduled in the state before the end of the year.

The reduction in executions and in the number of states that are enforcing death sentences led Supreme Court Justice Ruth Bader Ginsburg to conclude recently, “I think the death penalty is fading away.” There is not enough support on the court to abolish capital punishment, Ginsburg said, but added that may not be necessary.

“Most states don’t have any executions. The executions that we have are very heavily concentrated in a few states and even a few counties within those states,” she said in an interview with The Associated Press in July. Ginsburg joined a lengthy dissenting opinion by Justice Stephen Breyer last year that highlighted problems with the death penalty that led the two justices to conclude that it probably is unconstitutional.

States that have had to halt executions, though, are trying to figure out how to resume. Ohio and Oklahoma are among states that intend to re-start executions once they have corrected well-publicized problems in their death chambers.

Ohio, which last executed an inmate in January 2014, has set a January 12 execution date for a man convicted of raping and killing a three-year-old girl in Akron. But it’s unclear whether his execution, or more than two dozen others that are scheduled into 2020, will take place because the state lacks lethal execution drugs and has struggled to find a supplier, as have other states.

In Ohio’s last execution, in January 2014, Dennis McGuire gasped and snorted repeatedly during a 26-minute execution that used a never before tried combination of two drugs. That protocol has since been eliminated and those drugs aren’t available for executions.

Oklahoma last execution was in January 2015, amid the use of the wrong drug and other problems. The state’s prison system is expected to adopt new execution procedures soon. Even then, Attorney General Scott Pruitt says he will wait at least another five months before asking a court to schedule an execution.

Oklahoma imposed a moratorium on the death penalty after two problem-filled executions and a third that was called off when prison officials noticed they received the wrong drug. The top lawyer for Gov. Mary Fallin urged officials to go forward anyway, telling another lawyer to “Google it” to confirm the drug could be used, according to a grand jury investigation.

Alabama and Florida haven’t put anyone to death since January because of questions about the way death sentences are imposed in those states.

Even Texas has seen a reduction in executions. The state’s highest criminal appeals court has stopped four executions in the past month, though each case raised different issues. Separately, the Supreme Court will take up two Texas death row cases in the coming months, also involving discrete issues.

California has the largest death-row population, 746 inmates as of early August, but hasn’t executed anyone in 10 years. Voters in the nation’s most populous state will consider separate ballot questions in November that would abolish the death penalty on the one hand and speed up the appeals process on the other.

The longer states go without executions, the harder it may be for them to resume, said Robert Dunham, executive director of the Death Penalty Information Center.

“The law of inertia is that a body in motion tends to stay in motion. A body at rest tends to stay at rest. There are policy parallels for that with the death penalty. Right now most states are comfortable not executing anybody. And for the most part, the public is comfortable, even in death penalty states, with their states not executing anybody,” Dunham said.

So far there have been 15 executions this year. At the current pace, there would be 19 executions by the end of 2016, the fewest since 1991, when 14 people were put to death. The high-water mark was in 1999, when there were 98 executions.

The number of new death sentences also is approaching historic lows as most jurisdictions are forgoing costly capital trials in favor of seeking life sentences with no chance of parole. Texas, which has executed more people since the modern resumption of the death penalty in 1976 than the next six states combined, had only two new death sentences last year.

Many of the executions that are being carried out are for crimes committed up to 30 years ago, before some states enhanced the legal representation in capital cases, said Stephen Bright, an experienced death penalty lawyer who is president of the Southern Center for Human Rights.

“There are a lot of people who are getting executed who would never be sentenced to death today,” Bright said.

Associated Press writers Sean Murphy in Oklahoma City and Andrew Welsh-Huggins in Columbus, Ohio, contributed to this report.