HOMESTEAD, Fla. - NASCAR chairman Brian France said Friday no disciplinary action will be taken against Kurt Busch while police in Delaware investigate a claim of domestic assault made by the driver's former girlfriend.

Patricia Driscoll has filed court documents asking a judge to order Busch to stay away from her and not contact her, and she claims Busch verbally and physically abused her, smashing her head against a wall three times. The allegations involve an incident inside his motorhome at a race at Dover International Speedway in September a week after the couple broke up.

Busch has not been charged and has continued to drive for Stewart-Haas Racing. He qualified second for Sunday's season finale at Homestead-Miami Speedway. Busch did not take questions Friday night about the assault claim.

"We are watching that case carefully," France said. "It's under review by law enforcement and others, and they have not made a decision on that regarding Kurt. So until they make some judgments on that investigation, it wouldn't be right of us to just intervene before they've even gotten the investigation completed. So that's our position. We'll respect their process. It's in their hands."

Stewart-Haas executive vice-president Joe Custer said the team was also awaiting word from the authorities.

"We have spoken to Kurt in depth regarding this matter and he has vehemently denied that it happened and assures us there is no truth to it whatsoever," Custer said. "At this point in time we are taking Kurt at his word and his status with the team is unchanged."

France said he was sensitive to the focus on domestic violence in a year in which the NFL in particular has been under scrutiny for its handling of cases involving former Baltimore Ravens running back Ray Rice and other players. The NFL has toughened its policy on domestic violence, requiring a six-game suspension without pay for a first offence.

U.S. Rep. Jackie Speier of California sent a letter to NASCAR President Mike Helton and Stewart-Haas asking for Busch's suspension. She also called for a NASCAR policy of suspending drivers accused of domestic violence until criminal proceedings end or there is a clear lack of evidence.

"Your response to these serious allegations has been totally inadequate," Speier wrote.

France said there are no changes planned to NASCAR's domestic dispute policy.

"If charges are filed, that will change our equation, and we will look at that," France said. "We realize the heightened awareness of this important topic, and our policies will reflect that as we go down. They'll reflect how serious it is."

Speier also took aim at the handling of driver Travis Kvapil's arrest last year. Kvapil continued to race after he was arrested on charges of misdemeanour assault and false imprisonment against his wife.

"Unfortunately, NASCAR was equally passive" in handling Kvapil's arrest, she wrote.

NASCAR did not take disciplinary action against Tony Stewart while a grand jury considered and ultimately decided against charges for the Aug. 9 accident that killed sprint car driver Kevin Ward Jr.

"We don't think, for an event that wasn't even ours, that we would somehow come out and extract punishment from him, for something that authorities investigated very carefully, by the way," France said.