The FMCSA Drug & Alcohol Clearinghouse is a secure online database that gives employers, the FMCSA, state driver licensing agencies, and state law enforcement real-time access to information about CDL driver drug and alcohol program violations. Employers must query the Clearinghouse before hiring new CDL drivers (full query) and at least once annually for current drivers (limited query). Violations include positive drug tests, refusals, and other violations of 49 CFR Part 382. Drivers with unresolved violations cannot perform safety-sensitive functions until they complete the return-to-duty process.