There are not only various gradations of guilt in the commission of the same crime, which are not susceptible of any previous enumeration and definition; but the proofs must, in many cases, be imperfect in their own nature, not only as to the actual commission of the offence, but also, as to the aggravating or mitigating circumstances. In many cases, convictions must be founded upon presumpions and probabilities.
Would it not be at once unjust and unreasonable to exclude all means of mitigating punishment, when subsequent inquiries should demonstrate, that the accusation was wholly unfounded, or the crime greatly diminished in point of atrocity and aggravation, from what the evidence at the trial seemed to establish? A power to pardon seems, indeed, indispensable under the most correct administration of the law by human tribunals; since, otherwise, men would sometimes fall a prey to the vindictiveness of accusers, the inaccuracy of testimony, and the fallibility of jurors and courts.
Besides; the law may be broken, and yet the offender be placed in such circumstances, that he will stand, in a great measure, and perhaps wholly, excused in moral and general justice, though not in the strictness of the law. What then is to be done? Is he to be acquitted against the law; or convicted, and to suffer punishment infinitely beyond his deserts?