49 U.S.C. § 60121: Actions by private persons

may bring the action only after 60 days after the person has given notice of the violation to the Secretary of Transportation or to the appropriate State authority (when the violation is alleged to have occurred in a State certified under section 60105 of this title ) and to the person alleged to have committed the violation; may not bring the action if the Secretary or authority has begun and diligently is pursuing an administrative proceeding for the violation; and may not bring the action if the Attorney General of the United States, or the chief law enforcement officer of a State, has begun and diligently is pursuing a judicial proceeding for the violation. The Secretary shall prescribe the way in which notice is given under this subsection. The Secretary, with the approval of the Attorney General, or the Attorney General may intervene in an action under paragraph (1) of this subsection. based on the actual time spent and the reasonable expenses of the attorney for legal services provided to a person under this section; and computed at the rate prevailing for providing similar services for actions brought in the court awarding the fee. In this section, a violation of a safety standard or practice of a State is deemed to be a violation of this chapter or a regulation prescribed or order issued under this chapter only to the extent the standard or practice is not more stringent than a comparable minimum safety standard prescribed under this chapter. A remedy under this section is in addition to any other remedies provided by law. This section does not restrict a right to relief that a person or a class of persons may have under another law or at common law.