Every interpreter credential worth relying on is checkable against a public roster, usually in under five minutes. Verification matters because the consequence of an unverified claim lands on the proceeding, not the interpreter: testimony taken through an unqualified interpreter invites objection, exclusion, or a repeat performance. And the claims are not interchangeable. Certified, registered, qualified, and credentialed describe different tiers issued by different bodies, and a scheduling email that uses them loosely is exactly the situation verification exists for. The walkthrough below covers each roster in the order you are likely to need it.
Get the exact credential and jurisdiction in writing
Start by asking the interpreter or agency for three things in writing: the interpreter's full name as it appears on the credential, the exact credential tier, and the issuing jurisdiction or body. Vague answers like "court qualified" or "fully certified" are not credentials; they are adjectives. The distinctions between tiers are explained in what is a certified court interpreter.
Check the state court roster
For California court and deposition work, the Judicial Council publishes a searchable roster of certified and registered interpreters on the California Courts website. A certified interpreter appears there by name and language; so does a registered interpreter in languages without a certification exam. Details of the California program are in the California Court Interpreter Program explained, and other states' equivalents are cataloged in the state court interpreter certification guide.
Check the federal list for FCICE certification
Federal court certification is separate from state certification. The Federal Court Interpreter Certification Examination has been administered for Spanish, with historical certifications also existing for Haitian Creole and Navajo, and federally certified interpreters are listed for the district courts. If a matter is in federal court, state certification alone is not the same credential; the differences are covered in federal court interpreter certification explained.
Check the medical registries
Medical interpreter credentials have their own certifying bodies. CCHI offers credential verification for its Certified Healthcare Interpreter and associate-level credentials, and NBCMI maintains a registry of Certified Medical Interpreters. For an IME, AME, or clinical encounter, one of these two is the checkable standard; the comparison is in CCHI vs. NBCMI.
Check RID for sign language credentials
For American Sign Language, the Registry of Interpreters for the Deaf maintains a searchable directory of members and their certifications. Legal and medical ASL work should be staffed by RID-certified interpreters, and some situations call for a Certified Deaf Interpreter working in tandem, as described in when a Certified Deaf Interpreter is needed.
Apply the workers' compensation standard
California workers' comp uses its own definition. For hearings, depositions, and arbitrations, 8 CCR section 9795.1.5 recognizes interpreters on the State Personnel Board or California Courts listings; for medical evaluations, CCHI and NBCMI credentials also qualify. The fee schedule and credential rules are detailed in workers' comp interpreter credentials and fees.
Confirm it on the record
Verification ends where the transcript begins. In a California deposition, the interpreter states the credential on the record before testimony starts, which converts your verification into evidence. What that statement must contain, and what to do when it is missing, is covered in what a deposition interpreter must state on the record.
When verification fails, substitute before the proceeding, not after the objection. A replacement booked two days early is an inconvenience; an interpreter successfully challenged mid-deposition is a continuance, a second appearance fee, and sometimes a fight over the testimony already taken. AMS confirms every interpreter by name and credential in writing at booking, so the verification step is done before you receive the confirmation. Request a quote for any matter where the credential has to hold.