The Clearinghouse is a centralized database that employers use to report drug and alcohol program violations and to conduct queries, which check that current or prospective employees are not prohibited from performing safety-sensitive functions, such as operating a commercial motor vehicle (CMV), due to an unresolved drug and alcohol program violation—that is, a violation for which the driver has not completed the return-to-duty (RTD) process. Queries must be conducted as part of a pre-employment driver investigation, and at least annually for current employees.

In addition, employers may designate a C/TPA who can report violations and/or conduct queries on their behalf. An owner-operator—an employer that employs himself or herself as a CDL driver, typically a single-driver operation—must designate the C/TPA in the Clearinghouse.

To complete the actions outlined above, employers and C/TPAs are required to register in the Clearinghouse.