[In England] after 1170, … as part of the Compromise of Avranches, Henry … agreed that the secular courts, with few exceptions (high treason being one of them), had no jurisdiction over the clergy. … Defendants demonstrated their clerical status by reading from the Bible. This opened the door to literate lay defendants’ also claiming the benefit of clergy. In 1351 … the benefit of clergy was officially extended to all who could read. …
The Biblical passage traditionally used … [was the first verse of] Psalm 51 [which] …. became known as the neck verse, because knowing it could save one’s neck by transferring one’s case from a secular court, where hanging was a likely sentence, to an ecclesiastical court, … [where] if the defendant swore an oath to his own innocence and found twelve compurgators to swear likewise … he was acquitted. … By the 15th century, most convictions in these courts led to a sentence of penance. …
Henry VII decreed that non-clergymen should be allowed to plead the benefit of clergy only once … [and] were branded on the thumb, and the brand disqualified them from pleading the benefit of clergy in the future. (In 1547, the privilege of claiming benefit of clergy more than once was extended to peers [i.e., Nobleman] of the realm, even illiterate ones.)
In 1512, Henry VIII further restricted the benefit of clergy by making certain offences “unclergyable” offenses; … This restriction was condemned by Pope Leo X … [and led] to Henry VIII splitting the Church of England from the Roman Catholic Church in 1532. In 1575, a statute of Elizabeth I … the benefit of clergy … it did not nullify the conviction, but rather changed the sentence for first-time offenders from probable hanging to branding and up to a year’s incarceration.
More here. The English literate classes had quite a conspiracy going to help themselves at the expense of others! HT Greg Clark.
Added 11a: From stats Clark showed in a talk, it seems most folks people did not invoke this benefit. This was not a benefit given to all.
The English literate classes had quite a conspiracy going to help themselves at the expense of others!
Egad! Never thought they would be so blatant. They even added the illiterate peers into the mix to preserve their privileges.
Another thing to have in mind is that English post-Reformation legal authors viewed the medieval origins of the benefit of clergy with a strong anti-Catholic bias, and this has undoubtedly colored the modern views at least somewhat. For example, Blackstone introduces the topic with a hilariously cartoonish King-good-Pope-bad outburst:
Clergy, the privilegium clericale, or, in common speech, the benefit of clergy, had its original from the pious regard paid by Christian princes to the church in its infant state, and the ill use which the popish ecclesiastics soon made of that pious regard. The exemptions which they granted to the church were principally of two kinds: 1. Exemption of places consecrated to religious duties from criminal arrests, which was the foundation of sanctuaries. 2. Exemption of the persons of clergymen from criminal process before the secular judge in a few particular cases, which was the true original and meaning of the privilegium clericale.But the clergy, increasing in wealth, power, honour, number, and interest, began soon to set up for themselves; and that which they obtained by the favour of the civil government they now claimed as their inherent right, and as a right of the highest nature, indefeasible, and jure divino. By their canons therefore and constitutions they endeavoured at, and where they met with easy princes obtained, a vast extension of these exemptions, as well in regard to the crimes themselves, of which the list became quite universal, as in regard to the persons exempted, among whom were at length comprehended not only every little subordinate officer belonging to the church or clergy, but even many that were totally laymen.In England, however, although the usurpations of the pope were very many and grievous till Henry the Eighth entirely exterminated his supremacy, yet a total exemption of the clergy from secular jurisdiction could never be thoroughly effected...
In any case, the medieval power struggles between the Church and secular rulers that resulted (among many other things) in the English institution of the benefit of clergy were much more complex than either Blackstone's simplistic anti-popish story or a mere class-solidarity conspiracy of the literate. It's questionable if the real history of this institution can even be written given what we know today.