Wake County District Attorney Colon Willoughby confirmed for WRAL that there is not enough significant evidence to support a case against Jon Black.
Willoughby said the State Bureau of Investigation interviewed several people about Black's company, which won contracts to provide pest control services at three state prisons.
The probe began after a subcontractor said he was ordered to hire Black Pest Control to satisfy an unidentified lawmaker whose vote helped get the prisons built. Willoughby said the SBI was unable to corroborate that claim.
Jim Black is serving a federal prison sentence on corruption charges unrelated to the prison contracts.