Delaware's Justice Department said Thursday it would not prosecute Kurt Busch in connection with allegations by his ex-girlfriend, but the driver remained suspended indefinitely by NASCAR.
The agency said it found that "the admissible evidence and available witnesses would likely be insufficient to meet the burden of establishing beyond a reasonable doubt that Mr. Busch committed a crime."
Busch's ex-girlfriend, Patricia Driscoll, alleged that she was physically abused by Busch last Sept. 26 during an argument in Busch's motor home at Dover (Del.) International Speedway.
She filed a complaint with Dover police on Nov. 5, leading to a review by Delaware's Justice Department on whether Busch should face criminal charges.
In the meantime, a family court commissioner in Kent County granted Driscoll a no-contact order against Busch, 36, a former champion in NASCAR's Sprint Cup Series.
The commissioner, David W. Jones, also released a 25-page report on Feb. 20 in which he stated it was "more likely than not" that Busch had abused Driscoll by holding her throat and smashing her head against a wall in the motor home.
That prompted NASCAR to suspend Busch indefinitely.
Busch, who drives the No. 41 Chevrolet for Stewart-Haas Racing, has denied the allegations and he twice unsuccessfully appealed NASCAR's suspension.
NASCAR said it has since provided Busch with guidelines, which were not disclosed, for being reinstated as a driver in the Cup series and that Busch accepted them.
The sanctioning body said Thursday that "the elimination of the possibility of criminal charges certainly removes a significant impediment to his reinstatement."
Busch said Thursday he was "grateful" for the decision by the Justice Department. "As I have said from the beginning, I did not commit domestic abuse," Busch said in a statement. "I look forward to being back in racing as soon as possible and moving on with my life."
Driscoll also issued a statement, saying that "I am disappointed that full justice was not served here" but that she and her family "take a measure of solace" from Jones' no-contact order.
Busch missed the season-opening Daytona 500 on Feb. 22 and a race last weekend in Atlanta. Regan Smith will again fill in for him Sunday at Las Vegas Motor Speedway.