(…)The simple answer, now upheld by the Supreme Court, is that translators write, and interpreters speak.
When Japanese professional baseball player Kouichi Taniguchi fell through a wooden deck at the Marianas Resort and Spa while on vacation in the Commonwealth of the Northern Mariana Islands, he unwittingly set in motion a chain of legal maneuvers that culminated this week when the Supreme Court handed down its ruling. The question presented before the highest court in the land, however, had nothing to do with construction codes, accident liability or even compensation for pain and suffering. The question presented is whether costs incurred in translating written documents are “compensation of interpreters” for purposes of 28 U.S.C. § 1920(6).[1]

“So what?” may well be your next question. But for translators and interpreters, a cadre of multilingual knowledge workers whose importance continues to grow daily in the globally connected 21^st century, and for those who rely on their services, calling things by their names matters. Clear definitions are important; they help ensure that all parties involved understand each other.
Consider Capitol Hill, home to this nation’s lawmakers. Representatives work in the House, while senators work in the Senate. The work they do is similar, but no senator would take kindly to being called a congressman, and no congressman would try to participate in a vote on the Senate floor, even though they both work in Congress.
A similar division of labor exists between translators and interpreters. Translators work with the written word. They translate international treaties. They translate seized documents from Al Qaeda and other terrorist groups. They have translated Harry Potter into at least 67 other languages.  In contrast, interpreters made the Nuremburg Trials possible by simultaneously interpreting witness testimony into and out of English, French, German and Russian for those present in the courtroom. Interpreters make it possible for our president to pick up the phone and speak with other world leaders. They work in countless emergency rooms across this country interpreting what doctors and patients say in life and death situations. A literary translator is of no more use to an emergency room doctor than a medical interpreter is to a company that wants to publish the English version of Stieg Larsson’s latest mystery novel.  The skills, disciplines, and job descriptions are quite distinct.
In its opinion, the Court stated that “both the ordinary and technical meanings of ‘interpreter,’ as well as the statutory context in which the word is found, lead to the conclusion that § 1920(6) does not apply to translators of written materials.”[2] More.

See: Interpret America