DURHAM, N.C. (AP) -- Novelist Michael Peterson will get a new trial in the death of his wife because a key investigator misled jurors about the strength of bloodstain evidence, a judge ruled Wednesday.

Peterson was convicted of first-degree murder in the 2001 death of Kathleen Peterson, who was found at the bottom of a bloody staircase in the couple's mansion. Peterson has maintained his wife died in an accidental fall.

Four of Peterson's children were in the front row of the courtroom when the judge announced his decision. He blew them a kiss as several members if the family sobbed with joy.

Judge Orlando Hudson ruled that former State Bureau of Investigation agent Duane Deaver misled jurors at Peterson's 2003 trial.

Deaver was fired by the agency in January after an independent audit found problems in 34 cases where he either misreported test results, withheld results that could have helped the defendant or overstated the strength of the evidence to help prosecutors.

Over the last week, defense lawyer David Rudolf presented witnesses to cast doubt on Deaver's credibility, including three of the agent's former colleagues.

Nationally recognized experts in bloodstain pattern analysis testified that Deaver used antiquated techniques and that he gave opinions before the jury that were not justified by a scientific examination of the evidence.

The defense also showed that Deaver greatly exaggerated his level of experience and expertise when he was certified to provide expert testimony.

In his closing argument Wednesday, Rudolf said Deaver's lies violated Peterson's right to a fair trial.

"There is no way to sugarcoat it," Rudolf said. "Deaver lied to this court and this jury multiple times."

The judge, who presided over the 2003 trial, has scheduled a 2:30 p.m. hearing to determine whether Peterson can be released pending his retrial.

Peterson's novels include the 1990 "A Time of War," an in-the-trenches look at the Vietnam War, and a 1995 sequel, "A Bitter Peace."