Concubinage and marriage in medieval canon law

The medieval canon law adopted an ambivaient attitude toward concubinage among the laity. While the canonists disapproved of concubinage on moral grounds, they sought to assimilate the status of the concubine to that of the married woman and thus to legitimize concubinous relationships. In this process of assimilation the canonists made use of the institution of clandestine marriage, which created problems of its own. The crucial difficulty lay in constructing a satisfactory system of proof, so that it would be clear whether or not a given couple should be treated as married, or whether they should be considered legally as unmarried. The Council of Trent abolished lay concubinage and clandestine marriage, but thereby created a system of marriage law flawed with defects almost as serious as those experienced under the medieval law.