Wake County District Attorney Colon Willoughby said he will not pursue a criminal investigation into allegations that former House Speaker Jim Black's son improperly won contracts to provide pest control for three state prison projects.

Willoughby said that the State Bureau of Investigation interviewed several people involved in the contracts that Centex Construction awarded to Black Pest Control, which is owned by Jon Black. "Based on those interviews, I do not think there's significant evidence to warrant a criminal investigation," he said.

In November, The News & Observer reported that Black Pest Control, a Charlotte company, had won the work despite charging roughly three times more for the work than the low bidder. George Zaborowski, a former project manager for a subcontractor at two of the prisons, said that he was ordered to hire Black Pest Control at its price to satisfy a state lawmaker whose vote was critical for the prisons' construction.

Zaborowski said the order came from two officials with Centex Construction. One prison was built in Greene County; another, in Bertie; and the third is nearing completion in Columbus.

Willoughby said no one the SBI interviewed corroborated Zaborowski's claims. The interviewees told the SBI that, while Black Pest Control was not the low bidder, Centex wanted it to do the work because it had performed well on other Centex projects. Centex has since been bought by Balfour Beatty Construction.

Black Pest Control had no experience with prisons, but Balfour officials told The N&O that Black Pest Control had done well on two bank branch projects.

Willoughby also said investigators could not link the prison contracts to specific legislation. The legislation that authorized the three prisons' construction exempted Centex from following public bid laws. It is unclear how that language was added shortly before the bill came up for a vote in the full House and Senate.

Willoughby declined to release the SBI's report.

Jim Black, a Mecklenburg Democrat, is serving a five-year prison sentence and has been ordered to pay a $1 million fine after pleading guilty to state and federal public corruption charges. The crimes are not related to the prison construction.