Paucapalea, Prologue to Summa, ed. Johann F. von Schulte (Giessen: 1890, repr. Aalen: 1965) 1: "Placitandi forma in paradiso primum videtur inventa, dum prothoplastus de inobedientiae crimine ibidem a domino interrogatus criminis relatione sive remotione usus culpam in coniugem removisse autumat dicens, 'mulier, quam dedisti, dedit mihi et comedi' (Genesis 3.12).  Deinde in veteri lege nobis tradita, dum Moyses in lege sua ait: 'In ore duorum vel trium testium stabit omne verbum'  (Deut. 19.15)." 

The form of pleading was first found in paradise when the first man was questioned about the crime of disobedience.  When the Lord questioned him about the report of the crime or of use he transfered the guilt to his wife by asserting "The wife whom you gave to me handed it to me and I ate it."  Finally in the Old Testament we learn that Moses stated in his law that "In the testimony of two or three witnesses one may find the truth."

Digestum novum, Bologna, Biblioteca del Collegio di Spagna 283, fol. 82v