Opponents of capital punishment in North Carolina have long contended that racial bias contaminates the decisions about which people convicted of murder are sentenced to death for their crimes.

Now a series of blistering reports about the State Bureau of Investigation’s shoddy practices has reinforced the other reason why many oppose the death penalty: The “guilty” may in fact be innocent.

What’s more, the two thingsshady investigations and racial biasmay be related, according to a legal brief filed in connection with an appeal of a murder conviction in Craven County.

“Conscious or unconscious bias,” says Theresa Newman, a Duke University law professor and co-director of the law school’s Wrongful Convictions Clinic, may skew cases at any point from the way evidence is handled to how prosecutors view it to how jurors receive it.

Newman is among a group of Advocates for the Wrongly Convicted whose brief in the Craven County case asks for a full hearing on the influence of race in all murder cases.

“Racial biases infect every step of a criminal proceeding, and their harmful effects are compounded along the way,” the brief states. “The biases that result in disproportionate numbers of nonwhites entering the criminal justice system in the first place also result in their being perceived more suspiciously, treated more aggressively, and tried less fairly … even though the discrimination at each step may be entirely subconscious.

“Racially biased police investigations and arrest practices thus lead to racially biased prosecutorial charging decisions, which lead to racially biased sentencing decisions,” it goes on.

The advocates include lawyers from Duke and Wake Forest law schools, as well as Darryl Hunt and Ronald Cotton, two black men who were wrongfully convicted of murder and rape, respectively, and later exonerated. Jennifer Thompson, a white woman who incorrectly identified Cotton as her attackerDNA evidence later proved that a different man was her assailantis also among the advocates.

Hunt, who also was exonerated based on DNA evidence after serving 19 years in prison for murder, reminded reporters at a press conference Monday that all but one of his jurors voted for the death penalty. “If one juror in my trial had voted the other way, I’d have been executed” by the time his lawyers turned up the evidence proving his innocence.

Since he was freed in 2004, Hunt has worked through a nonprofit organization he established and with the NAACP for reforms in the criminal justice system. He called Monday for the abolition of capital punishment in North Carolina, a position also taken by the NAACP.

Mark Rabil, a Wake Forest law school faculty member and assistant state capital defender who stood with Hunt from trial to exoneration, said Gov. Bev Perdue should commute every death-row prisoners’ sentence to life imprisonment in view of the revelations about corruption at the SBI.

Carol Turowski, a Wake Forest law professor and co-director of the law school’s Innocence and Justice Clinic, said Perdue should at least declare a moratorium on future executions.

“Agents’ Secrets,” a series of reports in The News & Observer in August, ripped the SBI’s investigative methods, citing numerous casesincluding murder casesin which analysts misrepresented, or even seemed to fabricate, evidence indicating defendants’ guilt and suppressed evidence pointing to their innocence.

The newspaper’s reports revealed that the SBI considers itself to be part of the prosecutorial team in adversary proceedings, not an independent agency that should bring all evidence to light.

The SBI is an arm of the N.C. Department of Justice, which is headed by Attorney General Roy Cooper, an elected official who is serving his third four-year term in office. As N&O reporters were closing in on him, Cooper on July 29 announced that he was removing his SBI director, Robin Pendergraft, though she’d done “an excellent job.” He has since replaced her with Greg McLeod, who was his political aide and lobbyist in the General Assembly.

An audit of SBI crime lab cases involving suspected blood evidence, commissioned by Cooper, indicated that analysts misrepresented evidence in at least 230 cases over 16 years from 1987 to 2003. Other SBI work, including the handling of witnesses and physical evidence other than blood, has not been audited. The N.C. Conference of District Attorneys last week called for a full audit of the SBI, and its president, Seth Edwards, supported a moratorium on executions in any death-penalty cases in which the SBI was involved.

The SBI was involved in Melvin White’s conviction and death sentence. The only physical evidence linking White to a pair of murders, according to Kristin Parks, one of his attorneys, were some bullets found at the scene and others collected later from his backyard in rural Craven County and from Arizona, where he subsequently moved. No gun was found, but an SBI analyst testified that the bullets all came from the same gun, a finding other experts say could not be made without the gun.

The SBI analyst did not explain his conclusion that the same gun fired all the bullets, despite marks on them that did not match, Parks said, nor did he introduce any photographs of the tested bullets at White’s trial.

Parks said the SBI ignored evidence that one of the two victims called the police repeatedly about someone other than White, expressing fear for her life.

White has always maintained his innocence. “To say that [the investigation] was inadequate would be an understatement,” Parks said. “From all the evidence we’ve seen, Melvin White just may be telling the truth.”

The appeal in White’s case and the advocates’ brief were filed after the Legislature passed the 2009 Racial Justice Act, which Perdue signed into law. It allows death-row defendants to argue that, but for racial bias, they would have been sentenced to life in prison, as most murder convictions are.

In the brief, the advocates argue that all three death-row inmates exonerated in North Carolina since 2007 were black: Levon “Bo” Jones, Glen Chapman and Jonathon Hoffman. All of their alleged victims were white. And in all three cases, “the death sentences were based on highly questionable or false evidence” that was eventually discredited.

Since 1973, seven death-row inmates have been exonerated. Only one was whiteAlan Gell. All seven victims were white.

Three facts make minorities more likely to receive death sentences, the brief contends, despite “weak evidence and shoddy investigations.” One is racial stereotyping. A second is eyewitness misidentification of the kind Ronald Cotton experienced. Black witnesses aren’t very good at recalling white faces, nor are whites good with black faces, they say. Jennifer Thompson, despite her determination to remember what her assailant looked like, didn’t recognize him when she saw him, she said. Instead, she wrongly identified Cotton.

A third factor is that minorities make easy targets for the police if they’re poor or poorly educated and can’t marshal the resources for an effective defense.

White’s appeal is just one of 151 filed by death-row inmatesout of 159 total. Advocates are asking Benjamin Alford, chief judge of Superior Court for Craven County, to schedule a full hearing in White’s case and assign a judge to hear it. They believe it’s the one best suited to raise the full range of issues that could dismantle the administration of capital punishment in North Carolina.