(SportsNetwork.com) - NASCAR driver Kurt Busch will not be charged with a crime by the Delaware attorney general amid domestic violence allegations.

The attorney general cited a lack of sufficient evidence in the case from last September at Dover International Speedway involving Busch and ex-girlfriend Patricia Driscoll.

It was just last month that Busch was suspended by NASCAR after a Delaware Family Court judge granted Driscoll a protective order, saying Busch more likely than not committed an act of domestic violence against her in his motorhome.

The criminal case, conducted with an investigation by the Dover, Delaware police, was separate from the family court ruling.

Busch was suspended Feb. 20 and missed the first two races of the Sprint Cup season, including the Daytona 500. Earlier this week, he agreed to NASCAR's conditions for reinstatement and has begun the process.

Regan Smith, a regular in the Xfinity Series, will remain the replacement driver for Busch in the No. 41 car this weekend at Las Vegas Motor Speedway.