A more thorough explanation:

Term: in modum probationis
Definition: In the form of proof. This phrase was used in the past to describe documents that someone provided to support their claim. Example: John was trying to prove that he owned a piece of land. He showed the court a map and a deed that were in modum probationis, meaning they were provided as proof. Explanation: In this example, John used documents that were in modum probationis to support his claim that he owned the land. This phrase was used in the past to describe documents that were provided as evidence in a legal case.