Nebraska's Legislature voted Wednesday to abolish the death penalty, overturning Republican Gov. Pete Ricketts' veto. The state's unicameral legislature overwhelmingly approved the measure in a series of three previous votes.
The repeal comes as other states have experienced complications with new lethal-injection cocktails. But Americans overall still support the practice.
Support for the death penalty has slowly fallen over the past couple of decades, from a high of 80 percent in favor in the mid-1990s to just over 60 percent currently, according to Gallup.
That is actually near a 40-year low, but the longer history of public opinion on the death penalty is much more unstable. Views of other social issues, like same-sex marriage or abortion, have told somewhat clearer stories. Americans increasingly approve of same-sex marriage and have remained relatively deadlocked on abortion for decades.
What accounts for this? Any number of complicated factors combine to affect Americans' views on the death penalty. Here are four potential explanations for the huge swings in Americans' opinions:
1. Fear. "There are spikes in death-penalty support appearing during particular eras of what can be described as fear mongering," contended Robert Dunham, executive director of the Death Penalty Information Center, a nonprofit organization that studies the policy. He explained that during the "red scare" of the 1950s, American support for the death penalty picked up. It fell off in the early 1960s, only to pick up again in the late 1960s and early 1970s after a rash of high-profile assassinations — Robert F. Kennedy and Martin Luther King Jr., for example, and the attempted assassination of George Wallace. All of that contributed to a national conversation about the death penalty as the Supreme Court in 1972 found some death penalty statutes to be unconstitutional (effectively ending the practice for several years), but a 1976 decision opened the doors again. Then, the racially charged political rhetoric on crime in the 1980s (think Willie Horton) likewise fueled that support, according to Dunham's explanation.
Conversely, if a culture of fear contributes to support of the death penalty, public distrust of the government turns people against the policy, Dunham explains. During the Vietnam War era, when people started to question the government's choices, they also questioned the death penalty as a valid form of punishment.
2. Violence. This is a case in which it's easy to read correlation as causation — shifts in American support for the death penalty look remarkably similar to those in the violent-crime rate since 1960. It's possible that as people perceive less crime happening, they also aren't as enthusiastic about meting out death as a punishment, but, of course, the direction (or size) of causality here is unclear.
3. Wrongful convictions and DNA. As of today, 153 death row inmates have been exonerated. And the resulting stream of news about wrongful convictions — and potential wrongful deaths — is one of the main reasons Dunham gives for the recent decline in death penalty support.
"As more and more executions occurred, more and more injustices came to light," Dunham said. "There are [also] serious concerns about the poor quality of representation. But a lot of people think that the trigger was really the development of DNA."
Indeed, as of 1991 — only shortly after the introduction of DNA evidence in criminal trials — only 11 percent of people opposed to the death penalty told Gallup it was because of possible wrongful convictions. By 2003, 25 percent gave this as their answer, though the share has fallen some to 17 percent since then.
4. It's costly. Republicans remain far more likely to support the death penalty than Democrats, but support has fallen off among both parties, as well as independents, since the mid-1990s. Indeed, both Republicans and Democrats in the Nebraska Legislature voted against the death penalty. One reason those Republicans gave is the cost of executions, as NPR reported.
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