Which law first defined "qualified interpreter"

I’m building a 15-minute retrieval warm-up for our interpreter ethics unit and want to double-check my key: which U.S. law first defined the term “qualified interpreter” — Section 504 or the ADA — and if you know it, the exact citation (e.g., 28 CFR number) helps me model source-based curriculum design. I’m leaning ADA, but I want learners to see how we verify terminology, not just memorize it.

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ADA gets the trophy: DOJ defines “qualified interpreter” in 28 CFR 35.104 (Title II) and 28 CFR 36.104 (Title III) as “able to interpret effectively, accurately, and impartially.” 504 regs used the phrase earlier but didn’t define it; for class, I drop this link in slides so students can see the source: eCFR :: 28 CFR Part 35 -- Nondiscrimination on the Basis of Disability in State and Local Government Services. I keep that citation on a sticky note during ethics warm-ups.

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But you’re right to lean ADA; DOJ’s Title II and III regs were the first to spell out “qualified interpreter” (including “using any necessary specialized vocabulary”). See the definition section (.104) here: eCFR :: 28 CFR 35.104 -- Definitions., then have learners spot the parallel in Title III. Section 504 mentions auxiliary aids but didn’t lock in that definition, though some agencies later synced their 504 rules to the ADA — like peeking at the answer key before a pop quiz.

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