It’s simple: translation is used for the written word, such as documents, and interpretation is spoken out loud, such as simultaneous and consecutive interpretation.
No. In fact, most professional translators never interpret and most interpreters do not translate. They are two very unique skills.
Translators are needed to translate court documents to be presented as evidence or sworn affidavits. Interpreters are needed for depositions or other in-person hearings.
Yes and no. We have a national certification and can translate in all federal, state and local courts. States and cities have their own certifications and assessments for voice interpreters.