Written by Mary Brennan And Richard Brown. The Durham University research project observed court cases involving Deaf people over a three year period, and carried out in-depth interviews with Deaf people and interpreters. This revealed that sign language court interpreters are often not qualified interpreters, or have had no specialist legal interpreting training. The highly skilled task is often poorly understood by other participants in court proceedings, and the difference between BSL and English imposes particular constraints and demands on the interpreter.