information:classification
Blackstone's Ratio or Blackstone's Formulation

Among the most well-known of Blackstone's contributions to judicial theory is his own statement of the principle that it "is better that ten guilty persons escape than that one innocent suffer."

While this argument originates at least as far back as Genesis 18:23–32 in the Bible, as well as versions by Maimonides and Sir John Fortescue, Blackstone's analysis is the one picked up by Benjamin Franklin and others, so that the term has become known as "Blackstone's Ratio".

As John Adams, having studied Blackstone, put it:

It is more important that innocence should be protected, than it is, that guilt be punished; for guilt and crimes are so frequent in this world, that all of them cannot be punished.... when innocence itself, is brought to the bar and condemned, especially to die, the subject will exclaim, 'it is immaterial to me whether I behave well or ill, for virtue itself is no security.' And if such a sentiment as this were to take hold in the mind of the subject that would be the end of all security whatsoever.

Blackstone's Ratio is a maxim of English law, having been established as such within a few decades of Blackstone's work being published. It is also cited in courts and law in the US, and is strongly emphasised to American law students.