as soon as the proofs of a crime and its reality are fully certified, the criminal must be allowed time and opportunity for his defence; but the time allowed must be so short as not to interfere with the speediness of his punishment, which, as we have seen, is one of the principal restraints from crime. a false philanthropy seems opposed to this shortness of time; but all doubt will vanish, on reflection that the more defective any system of law is, the greater are the dangers to which innocence is exposed.

but the laws should fix a certain space of time both for the defence of the accused and for the discovery[158] of proofs against him. it would place the judge in the position of a legislator were it his duty to fix the time necessary for the latter. in the same way those atrocious crimes, whose memory tarries long in men’s minds, deserve, when once proved, no prescription in favour of a criminal who has fled from his country; but lesser and obscure crimes should be allowed a certain prescription, which may remove a man’s uncertainty concerning his fate, because the obscurity in which for a long time his crimes have been involved deducts from the bad example of his impunity, and the possibility of reform meantime remains to him. it is enough to indicate these principles, because i cannot fix a precise limit of time, except for a given system of laws and in given social circumstances. i will only add that, the advantage of moderate penalties in a nation being proved, the laws which shorten or lengthen, according to the gravity of crimes, the term of prescription or of proofs, thus making of prison itself or of voluntary exile a part of the punishment, will supply an easy classification of a few mild punishments for a very large number of crimes.

but these periods of time will not be lengthened in exact proportion to the atrocity of crimes, since the probability of a crime is in inverse ratio to its atrocity. it will, then, be necessary to shorten the period for inquiry and to increase that of prescription; which[159] may appear to contradict what i said before, namely, that it is possible to inflict equal penalties on unequal crimes, by counting as a penalty that period of imprisonment or of prescription which precedes the verdict. to explain to the reader my idea: i distinguish two kinds of crimes—the first, atrocious crimes, beginning with homicide and including all the excessive forms of wickedness; the second comprising less considerable crimes. this distinction is founded in human nature. personal security is a natural right, the security of property a social one. the number of motives which impel men to violate their natural affections is far smaller than those which impel them, by their natural longing for happiness, to violate a right which they do not find written in their hearts but only in the conventions of society. the very great difference between the probability of these two kinds of crime respectively makes it necessary that they should be ruled by different principles. in cases of the more atrocious crimes, because they are more uncommon, the time for inquiry ought to be so much the less as the probability of the innocence of the accused is greater; and the time of prescription ought to be longer, as on an ultimate definite sentence of guilt or innocence depends the destruction of the hope of impunity, the harm of which is proportioned to the atrocity of the crime. but in cases of lesser criminality, where the presumption in favour of a man’s[160] innocence is less, the time for inquiry should be longer; and as the harm of impunity is less, the time of prescription should be shorter. but such a division of crimes ought, indeed, not to be admitted, if the danger of impunity decreased exactly in proportion to the greater probability of the crime. one should remember that an accused man, whose guilt or innocence is uncertain, may, though acquitted for lack of proofs, be subjected for the same crime to a fresh imprisonment and inquiry, in the event of fresh legal proofs rising up against him, so long as the time of prescription accorded by the laws has not been past. such at least is the compromise that i think best fitted to preserve both the liberty and the security of the subject, it being only too easy so to favour the one at the expense of the other, that these two blessings, the inalienable and equal patrimony of every citizen, are left unprotected and undefended, the one from declared or veiled despotism, the other from the turbulence of civil anarchy.

there are some crimes which are at the same time of common occurrence and of difficult proof. in them the difficulty of proof is equivalent to a probability of innocence; and the harm of their impunity being so much the less to be considered as their frequency depends on principles other than the risk of punishment, the time for inquiry and the period of prescription ought both to be proportionately less. yet[161] cases of adultery and pederasty, both of difficult proof, are precisely those in which, according to received principles, tyrannical presumptions of quasi-proofs and half-proofs are allowed to prevail (as if a man could be half-innocent or half-guilty, in other words, half-punishable or half-acquittable); in which torture exercises its cruel sway over the person of the accused, over the witnesses, and even over the whole family of an unfortunate wretch, according to the coldly wicked teaching of some doctors of law, who set themselves up as the rule and standard for judges to follow.

in view of these principles it will appear strange (to anyone who does not reflect, that reason has, so to speak, never yet legislated for a nation), that it is just the most atrocious crimes or the most secret and chimerical ones—that is, those of the least probability—which are proved by conjectures or by the weakest and most equivocal proofs: as if it were the interest of the laws and of the judge, not to search for the truth, but to find out the crime; as if the danger of condemning an innocent man were not so much the greater, the greater the probability of his innocence over that of his guilt.

the majority of mankind lack that vigour which is equally necessary for the greatest crimes as for the greatest virtues; whence it would appear, that both extremes are contemporaneous phenomena in nations[162] which depend rather on the energy of their government and of the passions that tend to the public good, than on their size and the constant goodness of their laws. in the latter the weakened passions seem more adapted to maintain than to improve the form of government. from which flows an important consequence, namely, that great crimes in a nation do not always prove its decline.