The obligation of law enforcement agencies to provide interpreters is founded not only in regulations and statutes, but in constitutional law as well. Courts have suppressed evidence obtained from deaf defendants when it was found that the Miranda advice of rights was not adequately communicated. In some cases where confessions were suppressed, the Miranda warnings had been conveyed in sign language beyond the defendant's level of comprehension. In other cases, the Miranda warnings were given in written form that was well beyond the defendant's reading level. Sometimes, confessions and other pieces of evidence were suppressed because the Miranda warnings were not given at all.
Securing an interpreter with an NAD or RID legal skills certificate allows for a timely explanation of rights, that includes careful explanation of every legal term and sign. Providing qualified interpreters is one way police departments can both prevent objections to the adequacy of the communication and comply with the Justice Department's ADA and Section 504 rules. Presentation of a printed advice of rights form without providing interpretation will seldom if ever be sufficient. Some police departments videotape all communications with deaf defendants in order to verify for the court that the rights warning was effectively communicated and that the interpreter acted properly.
Miranda Advice of Rights
In the landmark decision Miranda v. Arizona, the U.S. Supreme Court recognized that questioning by police in the stationhouse or jail is inherently coercive and undermines the privilege against self-incrimination. As a result of this decision, police are now required to "effectively inform" accused people of their constitutional rights before any questioning can take place. Without use of a qualified interpreter, most deaf people would not be able to fully understand their rights, and any waiver of their rights would not meet the Court's standard of being voluntary, knowing, and intelligent.
The standard written advice of rights form given to suspects before questioning requires a sixth- to eighth-grade reading comprehension level. Hearing people's ability to understand the rights set forth in this form is not seriously impaired by a reading deficiency, because they can be told out loud what is written on the form. The listening comprehension level of people with normal hearing and of people with reading problems usually exceeds their reading comprehension level. However, the reading level required by the Miranda warnings and advice of rights forms remains far above the reading comprehension of many deaf people for whom English is a second language. Police officers need to ensure that deaf people receive a careful explanation of their rights by a qualified sign language interpreter.