of challenge tried by the court; and, in challenges for favor, the finding of the court as to the fact whether the juror stands indifferent between the parties, is equally conclusive, as if found by triers.
But the sections quoted do, in our opinion, make a material change in the common law, bearing upon the precise question raised by this assignment of errors. The practice has grown up in this State for every juror when presented, in cases of felony, to be considered as having been challenged for cause by the attorney for the State. Triers are rarely demanded, and the matter is, sub silentio, referred to the court, no cause of challenge being formally stated by either party. The juror is sworn upon his voir dire, and examined by the court, or the parties under its direction, and if any cause of challenge be made to appear upon his examination, he is set aside as incompetent. Such seems to have been the course pursued in this case as to the jurors, Williams and Moore. The record shows expressly, that those jurors were challenged by the prisoner for cause, which though not specified, we must intend, trom the proceedings that followed, to have been for principal cause, that the juror had formed or expressed an opinion touching the issue to be tried. It seems to be settled at the common law, certainly as understood and practiced in this country, that where the challenge for principal cause is not sustained by proof, the same evidence may be admissible to support a challenge to the favor; because, for example, the opinion formed by the juror might not be such as the law would recognize to be cause of principal challenge, yet the fact that he had formed any opinion might be competent evidence in connection with other circumstances before the triers, to enable them to determine whether he really stood indifferent between the parties. See Freeman vs. The People, 4 Denio 34. People vs. Mather, 4 Wend. 234. The causes that may influence the triers of a challenge to the favor are, as it were, intangible; and notwithstanding the declaration of the juror, that his opinion was hypothetical or founded on rumor, and left no bias on his mind, the triers might
