Associated Press
In this Sept. 21, 2010 file photo is the main entrance way to San Quentin State Prison where the state's death row is located in San Quentin, Calif. While 62 percent of Americans support the death penalty, more death penalty opponents fear wrongful convictions, according to a new study by the Pew Research Center.

A majority of Americans still favor the death penalty, but reasons for opposition are changing, according to a study by the Pew Research Center.

According to the study, 62 percent of adults in America favor the death penalty for people convicted of murder, and 31 percent are opposed. While such numbers have been consistent for the past seven years, the reasoning behind death penalty opposition has changed.

"When asked why they oppose the death penalty, 27 percent of opponents say it is wrong or immoral to kill someone, while an identical percentage (27 percent) cite concerns about flaws in the justice system and the possibility that innocent people could be put to death," said the report.

In a Gallup survey 20 years ago, a much higher percentage of death penalty opponents (41 percent) cited moral considerations, and only 11 percent mentioned problems with the justice system or wrongful executions.

Increased technology, particularly in regards to DNA testing, has led to more exonerations of people convicted of crimes. Since 1973, 142 people have been released from death row because of innocence.

Roughly half of those who support the death penalty do so because it is a "deserved/appropriate punishment," which is consistent with polling for the past few years.

Support for the death penalty in America peaked in 1996, when 78 percent of those polled favored capital punishment for people convicted of murder. It has since declined.

Thirty-three states use the death penalty. More than 3,200 inmates are currently on death row in the U.S. Forty-three prisoners were executed in 2012 in nine states.