Legal Definitions - lex deraisnia

Lex deraisnia is a historical legal principle where an accused party would deny an accusation by demonstrating that the claim was illogical, unreasonable, or highly improbable. Essentially, it was a defense based on showing that the accusation defied common sense or the known facts of the situation, making it impossible or extremely unlikely that the accused committed the alleged act.

Here are some examples to illustrate this concept:

• Example 1: Physical Impossibility

  Imagine a medieval lord, Lord Alaric, is accused of leading a raid on a neighboring village that occurred on a specific night. Lord Alaric's defense, using the principle of lex deraisnia, would involve presenting irrefutable evidence, such as multiple credible witnesses and official records, proving he was attending a royal council meeting in a distant city, a journey of several days, at the exact time of the raid. His argument would be that it is physically impossible for him to have been in two places at once, thus rendering the accusation against reason and probability.

• Example 2: Against Established Character or Circumstance

  Consider a respected village elder, known for her wisdom and fairness, who is accused of secretly diverting the village's shared water supply for her personal use during a severe drought. Her defense, based on lex deraisnia, would highlight her long-standing reputation for communal responsibility, her personal involvement in organizing water distribution for all villagers, and the fact that her own fields were also suffering from the drought. The argument would be that it is highly improbable and against reason for someone of her character and in her circumstances to commit such a selfish and detrimental act against her own community.

• Example 3: Defying Logical Sequence of Events

  Suppose a merchant is accused of failing to deliver a specific shipment of rare spices that was promised to arrive by a certain date. The merchant's defense, employing lex deraisnia, would involve presenting official shipping manifests and port records demonstrating that the vessel carrying the spices had tragically sunk in a well-documented storm several weeks before the promised delivery date, with all cargo lost. The accusation of non-delivery, in this context, becomes unreasonable and improbable because it defies the logical sequence of events; one cannot deliver goods that no longer exist due to an act of nature.