— More than 15 years after his wife was killed and more than five years after his murder conviction was overturned, Mike Peterson has reached a plea deal to finally resolve the case, according to defense attorney David Rudolf.

"We have reached an agreement with the District Attorney’s Office that will resolve all charges pending against Mike Peterson," Rudolf said in an email to WRAL News. "This case will be over, and that’s what’s important."

Although Rudolf wouldn't elaborate on the deal, sources told WRAL News that Peterson has agreed to enter an Alford plea to a charge of voluntary manslaughter, receive a sentence less than the time he's already served in prison and effectively walk out of the courthouse a free man later this month.

The plea would end one of the most notorious and long-running criminal cases in the Triangle, one so complex that it became the subject of a television documentary.

On Dec. 9, 2001, Kathleen Peterson was found dead in a pool of blood at the bottom of a staircase in the couple's Durham mansion, and two years later, Mike Peterson was found guilty of beating her to death in one of the longest trials in North Carolina history and sentenced to life in prison without parole.

The 73-year-old novelist and one-time Durham mayoral candidate has always maintained his innocence, arguing that his wife died after falling down the staircase.

An Alford plea would allow him to continue to do so. Under such a plea, a defendant can maintain his or her innocence while acknowledging prosecutors have enough evidence for a conviction. However, Peterson will bre treated as guilty and be a convicted felon.

Kathleen Peterson's family has opposed an Alford plea in the past, insisting that Mike Peterson admit that he killed her. But the landscape of the case has shifted enough in recent years for them apparently to soften their stance and agree to the plea deal and avoid enduring another trial and the possibility that he could be acquitted, according to sources.

"For over 15 years, Michael Peterson has professed his false innocence. The family of Kathleen is awaiting his plea of guilt for the horrific beating that ended Kathleen's life," her sister, Candace Zamperini, said in a statement. "Michael Peterson will forever be treated as guilty and be a convicted felon. The only reason this will be over is because he is pleading his guilt."

Retrial would be far different

After losing repeated appeals, Peterson was finally granted a new trial in December 2011 when Superior Court Judge Orlando Hudson ruled that a key prosecution witness, former State Crime Lab blood analyst Duane Deaver, had lied on the stand during the 2003 murder trial.

Testimony from Deaver, who was fired from the crime lab after many of his findings were discredited in an outside investigation of the lab, likely wouldn't be the only evidence from Peterson's first trial to be excluded in a retrial.

Rudolf has asked that some of the more lurid portions of the first trial, such as Peterson's fascination with gay pornography and his emails to a male escort, which prosecutors said was a motive for Kathleen Peterson's murder, and the death of Elizabeth Ratliff, a Peterson acquaintance from the 1980s who also had been found dead at the bottom of a staircase, which prosecutors said suggested that Mike Peterson had carried out a similar crime in the past.

Peterson's defense also could be more difficult. Testing the 15-year-old evidence for DNA to suggest that someone else killed Kathleen Peterson – an alternative theory to the staircase tumble defense – is virtually impossible because items became intermingled with evidence from other cases while in storage after the 2003 trial.

Peterson tried to get the case against him dismissed by arguing that the mishandled evidence amounted to a violation of his constitutional right to a fair trial, but Hudson rejected that argument last fall.

Sources said that, because of all the changes since the first trial, it would be difficult to convict Peterson of first-degree murder again. A manslaughter conviction carries a maximum sentence of about five years in prison, and Peterson has already served eight years behind bars, meaning a plea to that charge would once again make him a convicted felon but would remove the cloud hanging over him of a possible return to prison.