Ecclesiastical tribunals rely heavily on proof by witnesses in marriage nullity trials to make a determination regarding the alleged nullity of a marriage. Indeed, canon law holds proof by witnesses in great esteem. However, the norms on proof by witnesses are not as clear as they seem. Tribunals often run into difficulties in interpreting and applying them. This book, therefore, is an attempt to shed more light on the norms governing testimonial proof. It seeks to provide answers to the following questions Who can and who cannot be a witness How and by whom is testimony to be taken How is the testimony to be evaluated How does a judge arrive at a moral certitude regarding the testimony given Consequently, this book investigates and comments on the norms contained in the Code of Canon Law and the Instruction Dignitas connubii governing proof by witnesses in marriage nullity trials. It examines the norms regarding the admissibility or rejection of witnesses, their examination, and the c