Of Evidence and the Proofs of a Crime, and of the Form of Judgment. 



The following general theorem is of great use determining the certainty of a 

fact. When the proofs of a crime are dependent on each other, that is, when 

the evidence of each witness, taken separately, proves nothing, or when all 

the proofs are dependent upon one, the number of proofs neither increase nor 

diminish the probability of the fact; foe the force of the whole is no 

greater than the force of that on which they depend, and if this fails, they 

all fall to the ground. When the proofs are independent on each other, the 

probability of the fact increases in proportion to the number of proofs; for 

the falsehood of the one does not diminish the veracity of another. 



It may seem extraordinary that I speak of probability with regard to crimes, 

which to deserve a punishment, must be certain. But this paradox will vanish 

when it is considered, that, strictly speaking, moral certainty is only 

probability, but which is called a certainty, because every man in his 

senses assents to it from an habit produced by the necessity of acting, and 

which is anterior to all speculation. That certainty which is necessary to 

decide that the accused is guilty is the very same which determines every 

man in the most important transactions of his life.



The proofs of a crime may be divided into two classes, perfect and 

imperfect. I call those perfect which exclude the possibility of innocence; 

imperfect, those which do not exclude this possibility. Of the first, one 

only is sufficient for condemnation; of the second, as many are required as 

form a perfect proof; that is to say, that though each of these, separately 

taken, does not exclude the possibility of innocence, it is nevertheless 

excluded by their union. It should be also observed, that the imperfect 

proofs, of which the accused, if innocent, might clear himself, and does not 

become perfect.



But it is much easier to feel this moral certainty of proofs than to define 

it exactly. For this reason, I think it an excellent law which establishes 

assistants to the principal judge, and those chosen by lot; for that 

ignorance which judges by its feelings is less subject to error than the 

knowledge or the laws which judges by opinion. Where the laws are clear and 

precise, the office of the judge is merely to ascertain the fact. If, in 

examining the proofs of a crime, acuteness and dexterity be required, if 

clearness and precision be necessary in summoning up the result, to judge of 

the result itself nothing is wanting but plain and ordinary good sense, a 

less fallacious guide than the knowledge, of a judge, accustomed to find 

guilty, and to reduce all things to an artificial system borrowed from his 

studies. Happy the nation where the knowledge of the law is not a science!



It is an admirable law which ordains that every man shall be tried by his 

peers; for, when life, liberty and fortune, are in question, the sentiments 

which a difference of rank and fortune inspires should be silent; that 

superiority with which the fortunate look upon the unfortunate, and that 

envy with which the inferior regard their superiors, should have no 

influence. But when the crime is an offence against a fellow-subject, one 

half of the judges should be peers to the accused, and the other peers to 

the person offended: so that all private interest, which, in spite of 

ourselves, modifies the appearance of objects, even in the eyes of the most 

equitable, is counteracted, and nothing remains to turn aside the direction 

of truth and the laws. It is also just that the accused should have the 

liberty of excluding a certain number of his judges; where this liberty is, 

enjoyed for a long time, without any instance to the contrary, the criminal 

seems to condemn himself. 



All trials should be public, that opinion, which is the best, or perhaps the 

only cement of society, may curb the authority of the powerful, and the 

passions of the judge, and that the people may say, "We are protected by the 

laws; we are not slaves"; a sentiment which inspires courage, and which is 

the best tribute to a sovereign who knows his real interest. I shall not 

enter into particulars. There may be some persons who expect that I should 

say all that can be said upon this subject; to such what I have already 

written must be unintelligible.