What if the person who is Deaf wants to use a family member to interpret?

The ADA regulations also say that a public entity or private business shall not rely on an accompanying adult except: "where the individual with a disability specifically requests that the accompanying adult interpret or facilitate communication, the accompanying adult agrees…and reliance on that adult is appropriate under the circumstances."

So if the person who is Deaf wants to bring a family member along to interpret, that’s OK. But it might not always be a good idea. For one thing, using a family member to interpret violates the patient’s privacy and patient/doctor confidentiality. 

Second, the family member may not understand medical terminology or how to interpret it.

Finally, a family member may choose not to interpret accurately what the patient or doctor is saying. They may not want to let the patient know how serious the condition is. Or they may be embarrassed by what the patient’s response and “tone it down” a bit.