Blackstone's ratio

In criminal law, Blackstone's ratio (more recently referred to sometimes as Blackstone's formulation) is the idea that:

It is better that ten guilty persons escape than that one innocent suffer.^[1]

as expressed by the English jurist William Blackstone in his seminal work Commentaries on the Laws of England, published in the 1760s.

The idea subsequently became a staple of legal thinking in jurisdictions with legal systems derived from English criminal law and continues to be a topic of debate. There is also a long pre-history of similar sentiments going back centuries in a variety of legal traditions.

In the United States, high courts in individual states continue to adopt specific numerical values for the ratio, often not 10:1. As of 2018, courts in 38 states had adopted such a position.^[2]