49 CFR 5.91: Duty to adjudicate proceedings promptly.

Agency attorneys should promptly initiate proceedings or prosecute matters referred to them. In addition, cases should not be allowed to linger unduly after the adjudicatory process has begun. Attorneys should seek to settle matters where possible or refer the case to a decision maker for proper disposition when settlement negotiations have reached an impasse. Absent the showing of unusual or extenuating circumstances, or if necessitated for good cause, each OST component or OA with enforcement authority shall apply limiting principles to the duration of investigations. On-site investigations should generally be limited to 10 business days or less and enforcement staff shall make a decision on pursuing an administrative action within 30 days of the completion of the inspection or investigation and commence an enforcement action as soon as possible thereafter—unless otherwise required by statute.