A kind of witness is someone who provides evidence in a court of law. The four crossword solutions for this term are MATERIAL (8 letters), EXPERT (6 letters), STAR (4 letters), and EYE (3 letters). MATERIAL witnesses provide physical evidence such as documents or objects, while EXPERT witnesses provide specialized knowledge on a particular subject. STAR witnesses are those whose testimony is considered to be especially important or influential, while EYE witnesses are those who have seen an event firsthand.