RALEIGH, N.C. — Gov. Bev Perdue signed a bill into law Tuesday that prohibits race to determine whether someone faces the death penalty.

The General Assembly passed the North Carolina Racial Justice Act last week. That makes North Carolina the second state in the country that allows statistical evidence to establish racial bias as behind prosecutors seeking or jurors rendering the death penalty.

Kentucky is the other state.

"I have always been a supporter of death penalty, but I have always believed it must be carried out fairly,” Perdue said in a news release. “The Racial Justice Act ensures that when North Carolina hands down our state’s harshest punishment to our most heinous criminals – the decision is based on the facts and the law, not racial prejudice.”

The Senate voted 25-18 for a measure the NAACP and other advocates said was needed in a state that in less than three years has released three black men from prison who had been on death row.

"The need for this is critical and self-evident," Sen. Floyd McKissick, D-Durham, the bill's primary sponsor.

In one case cited by supporters, then-Gov. Mike Easley commuted the death sentence of Robert Bacon Jr. to life in prison in 2001. An all-white jury had sentenced him to death for stabbing his lover's husband to death. The woman, who is white and who lured her husband to the spot where he was killed, avoided a death sentence and has since been paroled.

The measure would allow judges to consider whether statistical data show race was a key factor in putting a defendant on trial for his life or receiving a death penalty. A judge who agrees with the evidence could limit a sentence to life in prison without parole.

District attorneys, sheriffs and victims advocates said the measure would make death penalty prosecutions too difficult. North Carolina has not had an execution in nearly three years.

For murder victims and their families, the bill "represents something ... that will end up reopening a lot of old wounds that were still waiting for complete closure," said Senate Minority Leader Phil Berger, R-Rockingham. "This also represents a significant departure from the jurisprudence that we have seen in North Carolina and the United States that says cases are to be decided by the facts of the case."

Since the state's last execution in August 2006, the number of prosecutors winning death penalty convictions has nearly come to a halt and public support for executions has waned.

Just one convict was sent to death row last year and five people have been acquitted of the charges that initially placed them on death row since 2000. Of the 59 capital convicts who had their cases retried this decade, only two were again sentenced to death.

A November 2005 poll from Elon University found that 64 percent of the state's adults supported capital punishment. The same poll found this March that 58 percent supported the death penalty while 28 percent opposed it. Less than half said this year that the death penalty was the most appropriate punishment for first-degree murder.

The North Carolina Conference of District Attorneys opposed the legislation. Forsyth County District Attorney Thomas Keith said lawmakers did not discuss that any local Superior Count judge's ruling finding a history of racial discrimination could lead other judges to apply the precedent statewide.

"The ultimate goal is to give an additional protection," for convicted murderers, Keith said.

Death row defendants would have one year to file a claim of racial bias in their death sentence.