By Brian Wellner

The wife of convicted killer Nicholas Sheley will testify at his upcoming trial, a judge ruled Tuesday, even as her credibility is being questioned.

Holly Sheley, 34, of Oregon, Ill., was arrested Aug. 17 on felony charges she sold heroin and awaits trial, according to court records.

Circuit Judge F. Michael Meersman said Tuesday he is concerned she may recant earlier testimony that Nicholas Sheley’s drug addiction was motive for his alleged killing spree.

“Her getting arrested for an alleged felony does not help your case,” Meersman told prosecutors. “There’s no telling what she’s going to say now.”

Sheley is accused of killing eight people in June 2008. He was convicted in August 2011 of first-degree murder in the death of Ronald Randall, 65, of Galesburg. He was sentenced to life in prison.

He now faces trial in Whiteside County on first-degree murder and other charges in the death of 93-year-old Russell Reed of Sterling. The two-week trial is still set to begin Oct. 22.

Holly Sheley testified at her husband’s trial last year, telling the jury he picked her up in a pickup the night of June 28, 2008, and she sat down in what appeared to be blood on the seat.

Prosecutors said the pickup belonged to Randall.

“She is obviously a very crucial witness,” Meersman said. “If she gets on the stand and waffles, it’s a real problem having her testify at all.”

Meersman directed prosecutors to question Holly Sheley ahead of her testifying in front of a jury.

“If she recants the whole story, both sides have a right to know that,” Meersman said.

Sheley still faces charges related to the deaths of four people in Rock Falls and an Arkansas couple who were killed while vacationing near St. Louis.